child class 计算十进制值之和并显示在 parent class asp.net core web api 的一对多关系中
Calculate sum of decimal values from child class and display in parent class in one to many relationships in asp.net core web api
我还是asp.net核心网络的新手api一对多关系，我有两个table：贷款和贷款历史
贷款模式
public class Loan
{
[Key]
public int LoanID { get; set; }
[DataType(DataType.Currency)]
[Column(TypeName = "money")]
public decimal LoanAmount { get; set; }
[DataType(DataType.Currency)]
[Column(TypeName = "money")]
[Display(Name = "Loan Balance")]
private decimal _LoanBalance;
public decimal LoanBalance
{
get
{
return LoanAmount *interestRate;
}
set { _LoanBalance = value; }
}
[Display(Name = "Interest Rate")]
public decimal interestRate { get; set; }
[DataType(DataType.Date)]
[DisplayFormat(DataFormatString = "{0:yyyy-MM-dd}", ApplyFormatInEditMode = true)]
[Display(Name = "Application Date")]
public DateTime ApplicationDate { get; set; }
[DataType(DataType.Date)]
[DisplayFormat(DataFormatString = "{0:yyyy-MM-dd}", ApplyFormatInEditMode = true)]
[Display(Name = "Disbursement Date")]
public DateTime DisbursmentDate { get; set; }
[DataType(DataType.Date)]
[DisplayFormat(DataFormatString = "{0:yyyy-MM-dd}", ApplyFormatInEditMode = true)]
[Display(Name = "Due Date")]
public DateTime DueDate { get; set; }
[Display(Name = "Defaulted")]
public bool Defaulted { get; set; }
[Display(Name = "Approved")]
public bool Approved { get; set; }
//Navigation property
public int CustomerID { get; set; }
public Customer customer { get; set; }
//public ICollection<LoanComments> loancomments { get; set; }
public ICollection<LoansHistories> loansHistories { get; set; }
}
LoanHistories 模型：
public class LoansHistories
{
[Key]
public int HistID { get; set; }
[DataType(DataType.Currency)]
[Column(TypeName = "money")]
[Display(Name = "Repaid Amount")]
public decimal RePaidIn { get; set; }
[DataType(DataType.Date)]
[DisplayFormat(DataFormatString = "{0:yyyy-MM-dd}", ApplyFormatInEditMode = true)]
[Display(Name = "Repayement Date")]
public DateTime RepayementDateDate { get; set; }
[Display(Name = "No of paying interest only")]
public int NoOfPayinyingIntrestOnly { get; set; }
//Navigation properties
public int LoanID { get; set; }
public Loan loan { get; set; }
}
生成如下Json数据
[{"loanID":1,"loanAmount":1000.0000,"loanBalance":15000.000000,"interestRate":15.00,"applicationDate":"2022-03-28T00:00:00","disbursmentDate":"2022-03-28T00:00:00","dueDate":"2022-04-28T00:00:00","defaulted":false,"approved":true,"customerID":30290122,"customer":null,"loansHistories":[{"histID":1,"rePaidIn":500.0000,"repayementDateDate":"2022-03-28T00:00:00","noOfPayinyingIntrestOnly":1,"loanID":1},{"histID":4,"rePaidIn":2000.0000,"repayementDateDate":"2022-03-21T00:00:00","noOfPayinyingIntrestOnly":1,"loanID":1},{"histID":5,"rePaidIn":50000.0000,"repayementDateDate":"2022-03-28T00:00:00","noOfPayinyingIntrestOnly":1,"loanID":1},{"histID":6,"rePaidIn":50000.0000,"repayementDateDate":"2022-03-28T00:00:00","noOfPayinyingIntrestOnly":5,"loanID":1},{"histID":7,"rePaidIn":50000.0000,"repayementDateDate":"2022-03-28T00:00:00","noOfPayinyingIntrestOnly":1,"loanID":1},{"histID":8,"rePaidIn":50000.0000,"repayementDateDate":"2022-03-28T00:00:00","noOfPayinyingIntrestOnly":1,"loanID":1},{"histID":10,"rePaidIn":200.0000,"repayementDateDate":"2022-03-28T00:00:00","noOfPayinyingIntrestOnly":8,"loanID":1}]},{"loanID":2,"loanAmount":3000.0000,"loanBalance":45000.000000,"interestRate":15.00,"applicationDate":"2022-03-28T00:00:00","disbursmentDate":"2022-03-28T00:00:00","dueDate":"2022-03-28T00:00:00","defaulted":false,"approved":true,"customerID":30290122,"customer":null,"loansHistories":[{"histID":2,"rePaidIn":2000.0000,"repayementDateDate":"2022-03-08T00:00:00","noOfPayinyingIntrestOnly":1,"loanID":2},{"histID":9,"rePaidIn":50000.0000,"repayementDateDate":"2022-03-28T00:00:00","noOfPayinyingIntrestOnly":2,"loanID":2}]},{"loanID":3,"loanAmount":1000.0000,"loanBalance":150.000000,"interestRate":0.15,"applicationDate":"2022-03-28T00:00:00","disbursmentDate":"2022-03-28T00:00:00","dueDate":"2022-03-28T00:00:00","defaulted":false,"approved":true,"customerID":30290122,"customer":null,"loansHistories":[]},{"loanID":4,"loanAmount":2000.0000,"loanBalance":2300.000000,"interestRate":1.15,"applicationDate":"2022-03-28T00:00:00","disbursmentDate":"2022-03-28T00:00:00","dueDate":"2022-03-28T00:00:00","defaulted":false,"approved":true,"customerID":30290122,"customer":null,"loansHistories":[{"histID":3,"rePaidIn":2000.0000,"repayementDateDate":"2022-03-28T00:00:00","noOfPayinyingIntrestOnly":1,"loanID":4},{"histID":11,"rePaidIn":2000.0000,"repayementDateDate":"2022-03-28T00:00:00","noOfPayinyingIntrestOnly":3,"loanID":4},{"histID":12,"rePaidIn":2000.0000,"repayementDateDate":"2022-03-28T00:00:00","noOfPayinyingIntrestOnly":6,"loanID":4},{"histID":13,"rePaidIn":2000.0000,"repayementDateDate":"2022-03-28T00:00:00","noOfPayinyingIntrestOnly":6,"loanID":4},{"histID":14,"rePaidIn":2000.0000,"repayementDateDate":"2022-02-27T00:00:00","noOfPayinyingIntrestOnly":7,"loanID":4},{"histID":15,"rePaidIn":2000.0000,"repayementDateDate":"2022-03-28T00:00:00","noOfPayinyingIntrestOnly":1,"loanID":4},{"histID":16,"rePaidIn":2000.0000,"repayementDateDate":"2022-03-14T00:00:00","noOfPayinyingIntrestOnly":6,"loanID":4},{"histID":17,"rePaidIn":2000.0000,"repayementDateDate":"2022-03-28T00:00:00","noOfPayinyingIntrestOnly":3,"loanID":4},{"histID":18,"rePaidIn":2000.0000,"repayementDateDate":"2022-03-22T00:00:00","noOfPayinyingIntrestOnly":8,"loanID":4}]},{"loanID":5,"loanAmount":1000.0000,"loanBalance":1150.000000,"interestRate":1.15,"applicationDate":"2022-03-28T00:00:00","disbursmentDate":"2022-03-29T00:00:00","dueDate":"2021-04-29T00:00:00","defaulted":false,"approved":true,"customerID":30290122,"customer":null,"loansHistories":[]},{"loanID":8,"loanAmount":3000.0000,"loanBalance":3450.000000,"interestRate":1.15,"applicationDate":"2022-04-25T00:00:00","disbursmentDate":"2022-03-28T00:00:00","dueDate":"2022-04-26T00:00:00","defaulted":false,"approved":true,"customerID":30290122,"customer":null,"loansHistories":[]},{"loanID":9,"loanAmount":1000.0000,"loanBalance":1150.000000,"interestRate":1.15,"applicationDate":"2022-04-13T00:00:00","disbursmentDate":"2022-04-04T00:00:00","dueDate":"2022-04-25T00:00:00","defaulted":false,"approved":true,"customerID":30290122,"customer":null,"loansHistories":[]},{"loanID":10,"loanAmount":3000.0000,"loanBalance":3450.000000,"interestRate":1.15,"applicationDate":"2022-04-19T00:00:00","disbursmentDate":"2022-04-26T00:00:00","dueDate":"2022-04-25T00:00:00","defaulted":false,"approved":true,"customerID":40140676,"customer":null,"loansHistories":[{"histID":1012,"rePaidIn":300.0000,"repayementDateDate":"2022-04-05T00:00:00","noOfPayinyingIntrestOnly":1,"loanID":10},{"histID":1013,"rePaidIn":150.0000,"repayementDateDate":"2022-04-19T00:00:00","noOfPayinyingIntrestOnly":2,"loanID":10},{"histID":1014,"rePaidIn":300.0000,"repayementDateDate":"2022-04-11T00:00:00","noOfPayinyingIntrestOnly":3,"loanID":10},{"histID":1015,"rePaidIn":150.0000,"repayementDateDate":"2022-04-11T00:00:00","noOfPayinyingIntrestOnly":4,"loanID":10},{"histID":1016,"rePaidIn":300.0000,"repayementDateDate":"2022-04-06T00:00:00","noOfPayinyingIntrestOnly":5,"loanID":10},{"histID":1017,"rePaidIn":150.0000,"repayementDateDate":"2022-04-04T00:00:00","noOfPayinyingIntrestOnly":6,"loanID":10},{"histID":1018,"rePaidIn":300.0000,"repayementDateDate":"2022-04-05T00:00:00","noOfPayinyingIntrestOnly":7,"loanID":10},{"histID":1019,"rePaidIn":150.0000,"repayementDateDate":"2022-04-19T00:00:00","noOfPayinyingIntrestOnly":8,"loanID":10},{"histID":1020,"rePaidIn":150.0000,"repayementDateDate":"2022-04-02T00:00:00","noOfPayinyingIntrestOnly":9,"loanID":10},{"histID":1021,"rePaidIn":150.0000,"repayementDateDate":"2022-04-04T00:00:00","noOfPayinyingIntrestOnly":10,"loanID":10},{"histID":1022,"rePaidIn":100.0000,"repayementDateDate":"2022-04-06T00:00:00","noOfPayinyingIntrestOnly":12,"loanID":10},{"histID":1023,"rePaidIn":350.0000,"repayementDateDate":"2022-04-04T00:00:00","noOfPayinyingIntrestOnly":13,"loanID":10},{"histID":1024,"rePaidIn":100.0000,"repayementDateDate":"2022-04-12T00:00:00","noOfPayinyingIntrestOnly":14,"loanID":10},{"histID":1025,"rePaidIn":350.0000,"repayementDateDate":"2022-04-11T00:00:00","noOfPayinyingIntrestOnly":6,"loanID":10},{"histID":1026,"rePaidIn":100.0000,"repayementDateDate":"2022-04-20T00:00:00","noOfPayinyingIntrestOnly":14,"loanID":10},{"histID":1027,"rePaidIn":1000.0000,"repayementDateDate":"2022-04-12T00:00:00","noOfPayinyingIntrestOnly":16,"loanID":10},{"histID":1028,"rePaidIn":1000.0000,"repayementDateDate":"2022-04-04T00:00:00","noOfPayinyingIntrestOnly":17,"loanID":10},{"histID":1029,"rePaidIn":1000.0000,"repayementDateDate":"2022-04-04T00:00:00","noOfPayinyingIntrestOnly":18,"loanID":10}]},{"loanID":11,"loanAmount":1000.0000,"loanBalance":1150.000000,"interestRate":1.15,"applicationDate":"2022-04-26T00:00:00","disbursmentDate":"2022-04-25T00:00:00","dueDate":"2022-04-05T00:00:00","defaulted":false,"approved":true,"customerID":30290122,"customer":null,"loansHistories":[{"histID":1030,"rePaidIn":150.0000,"repayementDateDate":"2022-04-05T00:00:00","noOfPayinyingIntrestOnly":1,"loanID":11},{"histID":1031,"rePaidIn":150.0000,"repayementDateDate":"2022-04-12T00:00:00","noOfPayinyingIntrestOnly":5,"loanID":11}]},{"loanID":12,"loanAmount":1000.0000,"loanBalance":1150.000000,"interestRate":1.15,"applicationDate":"2022-04-24T00:00:00","disbursmentDate":"2022-04-24T00:00:00","dueDate":"2022-04-25T00:00:00","defaulted":false,"approved":true,"customerID":40140676,"customer":null,"loansHistories":[{"histID":1032,"rePaidIn":150.0000,"repayementDateDate":"2022-04-04T00:00:00","noOfPayinyingIntrestOnly":1,"loanID":12},{"histID":1033,"rePaidIn":150.0000,"repayementDateDate":"2022-03-28T00:00:00","noOfPayinyingIntrestOnly":3,"loanID":12}]},{"loanID":13,"loanAmount":2000.0000,"loanBalance":2300.000000,"interestRate":1.15,"applicationDate":"2022-04-24T00:00:00","disbursmentDate":"2022-04-25T00:00:00","dueDate":"2022-05-03T00:00:00","defaulted":false,"approved":true,"customerID":30290122,"customer":null,"loansHistories":[{"histID":1034,"rePaidIn":300.0000,"repayementDateDate":"2022-03-28T00:00:00","noOfPayinyingIntrestOnly":1,"loanID":13},{"histID":1035,"rePaidIn":300.0000,"repayementDateDate":"2022-04-12T00:00:00","noOfPayinyingIntrestOnly":9,"loanID":13}]},{"loanID":14,"loanAmount":1000.0000,"loanBalance":1150.000000,"interestRate":1.15,"applicationDate":"2022-04-25T00:00:00","disbursmentDate":"2022-04-06T00:00:00","dueDate":"2022-04-26T00:00:00","defaulted":false,"approved":true,"customerID":30290122,"customer":null,"loansHistories":[{"histID":1036,"rePaidIn":150.0000,"repayementDateDate":"2022-04-05T00:00:00","noOfPayinyingIntrestOnly":1,"loanID":14},{"histID":1037,"rePaidIn":1000.0000,"repayementDateDate":"2022-04-04T00:00:00","noOfPayinyingIntrestOnly":4,"loanID":14},{"histID":1038,"rePaidIn":150.0000,"repayementDateDate":"2022-04-18T00:00:00","noOfPayinyingIntrestOnly":4,"loanID":14},{"histID":1039,"rePaidIn":1000.0000,"repayementDateDate":"2022-04-11T00:00:00","noOfPayinyingIntrestOnly":5,"loanID":14},{"histID":1040,"rePaidIn":100.0000,"repayementDateDate":"2022-04-19T00:00:00","noOfPayinyingIntrestOnly":6,"loanID":14},{"histID":1041,"rePaidIn":50.0000,"repayementDateDate":"2022-04-04T00:00:00","noOfPayinyingIntrestOnly":7,"loanID":14},{"histID":1042,"rePaidIn":50.0000,"repayementDateDate":"2022-04-05T00:00:00","noOfPayinyingIntrestOnly":8,"loanID":14},{"histID":1043,"rePaidIn":50.0000,"repayementDateDate":"2022-04-06T00:00:00","noOfPayinyingIntrestOnly":8,"loanID":14},{"histID":1044,"rePaidIn":1000.0000,"repayementDateDate":"2022-03-28T00:00:00","noOfPayinyingIntrestOnly":89,"loanID":14}]},{"loanID":1014,"loanAmount":5000.0000,"loanBalance":5750.000000,"interestRate":1.15,"applicationDate":"2022-03-28T00:00:00","disbursmentDate":"2022-04-11T00:00:00","dueDate":"2022-04-12T00:00:00","defaulted":false,"approved":true,"customerID":40140676,"customer":null,"loansHistories":[{"histID":2035,"rePaidIn":750.0000,"repayementDateDate":"2022-04-11T00:00:00","noOfPayinyingIntrestOnly":1,"loanID":1014},{"histID":2036,"rePaidIn":1000.0000,"repayementDateDate":"2022-04-12T00:00:00","noOfPayinyingIntrestOnly":2,"loanID":1014},{"histID":2037,"rePaidIn":750.0000,"repayementDateDate":"2022-03-30T00:00:00","noOfPayinyingIntrestOnly":3,"loanID":1014}]}]
现在我想计算 loanHistories table 中的 rePaidIn 总和并在贷款 table 中显示 TotalRepaidIn 标题为 [NotMapped]：我尝试了以下 link .it seems close to answer my question but it does not
这是我的控制器
[HttpGet]
public async Task<ActionResult<IEnumerable<Loan>>> Getloans()
{
return await _context.loans.Include(lh => lh.loansHistories).ToListAsync();
}
任何解决方案将不胜感激。提前致谢
这是一个完整的工作演示：
型号：
public class Loan
{
[Key]
public int LoanID { get; set; }
[DataType(DataType.Currency)]
[Column(TypeName = "money")]
public decimal LoanAmount { get; set; }
[DataType(DataType.Currency)]
[Column(TypeName = "money")]
[Display(Name = "Loan Balance")]
private decimal _LoanBalance;
[Column(TypeName = "decimal(18,2)")]
public decimal LoanBalance
{
get
{
return LoanAmount * interestRate;
}
set { _LoanBalance = value; }
}
[Column(TypeName = "decimal(18,2)")]
[Display(Name = "Interest Rate")]
public decimal interestRate { get; set; }
//....
[Display(Name = "Approved")]
public bool Approved { get; set; }
//public ICollection<LoanComments> loancomments { get; set; }
public ICollection<LoansHistories> loansHistories { get; set; }
[NotMapped]
public decimal TotalRepaidIn { get; set; } //add this...
}
public class LoansHistories
{
[Key]
public int HistID { get; set; }
[DataType(DataType.Currency)]
[Column(TypeName = "money")]
[Display(Name = "Repaid Amount")]
public decimal RePaidIn { get; set; }
[DataType(DataType.Date)]
[DisplayFormat(DataFormatString = "{0:yyyy-MM-dd}", ApplyFormatInEditMode = true)]
[Display(Name = "Repayement Date")]
public DateTime RepayementDateDate { get; set; }
[Display(Name = "No of paying interest only")]
public int NoOfPayinyingIntrestOnly { get; set; }
public int LoanID { get; set; }
public Loan loan { get; set; }
}
控制器：
public async Task<ActionResult<IEnumerable<Loan>>> Getloans()
{
var data = await _context.loans.Include(lh => lh.loansHistories).Select(l=>new Loan()
{
TotalRepaidIn = l.loansHistories.Select(lh=>lh.RePaidIn).Sum(),
loansHistories = l.loansHistories,
ApplicationDate = l.ApplicationDate,
Defaulted=l.Defaulted,
DisbursmentDate= l.DisbursmentDate,
DueDate= l.DueDate,
LoanID=l.LoanID,
Approved=l.Approved,
interestRate=l.interestRate,
LoanAmount=l.LoanAmount
}).ToListAsync();
return data;
}
更新：
更好的方法是像下面这样更改模型：
using System.Linq; //import this namespace...
public class Loan
{
[Key]
public int LoanID { get; set; }
[DataType(DataType.Currency)]
[Column(TypeName = "money")]
public decimal LoanAmount { get; set; }
private decimal _TotalRepaidIn;
[NotMapped]
public decimal TotalRepaidIn
{
get { return loansHistories.Sum(sum => sum.RePaidIn); }
set { _TotalRepaidIn = value; }
}
//other properties
public ICollection<LoansHistories> loansHistories { get; set; } = new List<LoansHistories>();
}
控制器：
public async Task<ActionResult<IEnumerable<Loan>>> Getloans()
{
return await _context.loans.Include(lh => lh.loansHistories).ToListAsync();
}
我还是asp.net核心网络的新手api一对多关系，我有两个table：贷款和贷款历史
贷款模式
public class Loan
{
[Key]
public int LoanID { get; set; }
[DataType(DataType.Currency)]
[Column(TypeName = "money")]
public decimal LoanAmount { get; set; }
[DataType(DataType.Currency)]
[Column(TypeName = "money")]
[Display(Name = "Loan Balance")]
private decimal _LoanBalance;
public decimal LoanBalance
{
get
{
return LoanAmount *interestRate;
}
set { _LoanBalance = value; }
}
[Display(Name = "Interest Rate")]
public decimal interestRate { get; set; }
[DataType(DataType.Date)]
[DisplayFormat(DataFormatString = "{0:yyyy-MM-dd}", ApplyFormatInEditMode = true)]
[Display(Name = "Application Date")]
public DateTime ApplicationDate { get; set; }
[DataType(DataType.Date)]
[DisplayFormat(DataFormatString = "{0:yyyy-MM-dd}", ApplyFormatInEditMode = true)]
[Display(Name = "Disbursement Date")]
public DateTime DisbursmentDate { get; set; }
[DataType(DataType.Date)]
[DisplayFormat(DataFormatString = "{0:yyyy-MM-dd}", ApplyFormatInEditMode = true)]
[Display(Name = "Due Date")]
public DateTime DueDate { get; set; }
[Display(Name = "Defaulted")]
public bool Defaulted { get; set; }
[Display(Name = "Approved")]
public bool Approved { get; set; }
//Navigation property
public int CustomerID { get; set; }
public Customer customer { get; set; }
//public ICollection<LoanComments> loancomments { get; set; }
public ICollection<LoansHistories> loansHistories { get; set; }
}
LoanHistories 模型：
public class LoansHistories
{
[Key]
public int HistID { get; set; }
[DataType(DataType.Currency)]
[Column(TypeName = "money")]
[Display(Name = "Repaid Amount")]
public decimal RePaidIn { get; set; }
[DataType(DataType.Date)]
[DisplayFormat(DataFormatString = "{0:yyyy-MM-dd}", ApplyFormatInEditMode = true)]
[Display(Name = "Repayement Date")]
public DateTime RepayementDateDate { get; set; }
[Display(Name = "No of paying interest only")]
public int NoOfPayinyingIntrestOnly { get; set; }
//Navigation properties
public int LoanID { get; set; }
public Loan loan { get; set; }
}
生成如下Json数据
[{"loanID":1,"loanAmount":1000.0000,"loanBalance":15000.000000,"interestRate":15.00,"applicationDate":"2022-03-28T00:00:00","disbursmentDate":"2022-03-28T00:00:00","dueDate":"2022-04-28T00:00:00","defaulted":false,"approved":true,"customerID":30290122,"customer":null,"loansHistories":[{"histID":1,"rePaidIn":500.0000,"repayementDateDate":"2022-03-28T00:00:00","noOfPayinyingIntrestOnly":1,"loanID":1},{"histID":4,"rePaidIn":2000.0000,"repayementDateDate":"2022-03-21T00:00:00","noOfPayinyingIntrestOnly":1,"loanID":1},{"histID":5,"rePaidIn":50000.0000,"repayementDateDate":"2022-03-28T00:00:00","noOfPayinyingIntrestOnly":1,"loanID":1},{"histID":6,"rePaidIn":50000.0000,"repayementDateDate":"2022-03-28T00:00:00","noOfPayinyingIntrestOnly":5,"loanID":1},{"histID":7,"rePaidIn":50000.0000,"repayementDateDate":"2022-03-28T00:00:00","noOfPayinyingIntrestOnly":1,"loanID":1},{"histID":8,"rePaidIn":50000.0000,"repayementDateDate":"2022-03-28T00:00:00","noOfPayinyingIntrestOnly":1,"loanID":1},{"histID":10,"rePaidIn":200.0000,"repayementDateDate":"2022-03-28T00:00:00","noOfPayinyingIntrestOnly":8,"loanID":1}]},{"loanID":2,"loanAmount":3000.0000,"loanBalance":45000.000000,"interestRate":15.00,"applicationDate":"2022-03-28T00:00:00","disbursmentDate":"2022-03-28T00:00:00","dueDate":"2022-03-28T00:00:00","defaulted":false,"approved":true,"customerID":30290122,"customer":null,"loansHistories":[{"histID":2,"rePaidIn":2000.0000,"repayementDateDate":"2022-03-08T00:00:00","noOfPayinyingIntrestOnly":1,"loanID":2},{"histID":9,"rePaidIn":50000.0000,"repayementDateDate":"2022-03-28T00:00:00","noOfPayinyingIntrestOnly":2,"loanID":2}]},{"loanID":3,"loanAmount":1000.0000,"loanBalance":150.000000,"interestRate":0.15,"applicationDate":"2022-03-28T00:00:00","disbursmentDate":"2022-03-28T00:00:00","dueDate":"2022-03-28T00:00:00","defaulted":false,"approved":true,"customerID":30290122,"customer":null,"loansHistories":[]},{"loanID":4,"loanAmount":2000.0000,"loanBalance":2300.000000,"interestRate":1.15,"applicationDate":"2022-03-28T00:00:00","disbursmentDate":"2022-03-28T00:00:00","dueDate":"2022-03-28T00:00:00","defaulted":false,"approved":true,"customerID":30290122,"customer":null,"loansHistories":[{"histID":3,"rePaidIn":2000.0000,"repayementDateDate":"2022-03-28T00:00:00","noOfPayinyingIntrestOnly":1,"loanID":4},{"histID":11,"rePaidIn":2000.0000,"repayementDateDate":"2022-03-28T00:00:00","noOfPayinyingIntrestOnly":3,"loanID":4},{"histID":12,"rePaidIn":2000.0000,"repayementDateDate":"2022-03-28T00:00:00","noOfPayinyingIntrestOnly":6,"loanID":4},{"histID":13,"rePaidIn":2000.0000,"repayementDateDate":"2022-03-28T00:00:00","noOfPayinyingIntrestOnly":6,"loanID":4},{"histID":14,"rePaidIn":2000.0000,"repayementDateDate":"2022-02-27T00:00:00","noOfPayinyingIntrestOnly":7,"loanID":4},{"histID":15,"rePaidIn":2000.0000,"repayementDateDate":"2022-03-28T00:00:00","noOfPayinyingIntrestOnly":1,"loanID":4},{"histID":16,"rePaidIn":2000.0000,"repayementDateDate":"2022-03-14T00:00:00","noOfPayinyingIntrestOnly":6,"loanID":4},{"histID":17,"rePaidIn":2000.0000,"repayementDateDate":"2022-03-28T00:00:00","noOfPayinyingIntrestOnly":3,"loanID":4},{"histID":18,"rePaidIn":2000.0000,"repayementDateDate":"2022-03-22T00:00:00","noOfPayinyingIntrestOnly":8,"loanID":4}]},{"loanID":5,"loanAmount":1000.0000,"loanBalance":1150.000000,"interestRate":1.15,"applicationDate":"2022-03-28T00:00:00","disbursmentDate":"2022-03-29T00:00:00","dueDate":"2021-04-29T00:00:00","defaulted":false,"approved":true,"customerID":30290122,"customer":null,"loansHistories":[]},{"loanID":8,"loanAmount":3000.0000,"loanBalance":3450.000000,"interestRate":1.15,"applicationDate":"2022-04-25T00:00:00","disbursmentDate":"2022-03-28T00:00:00","dueDate":"2022-04-26T00:00:00","defaulted":false,"approved":true,"customerID":30290122,"customer":null,"loansHistories":[]},{"loanID":9,"loanAmount":1000.0000,"loanBalance":1150.000000,"interestRate":1.15,"applicationDate":"2022-04-13T00:00:00","disbursmentDate":"2022-04-04T00:00:00","dueDate":"2022-04-25T00:00:00","defaulted":false,"approved":true,"customerID":30290122,"customer":null,"loansHistories":[]},{"loanID":10,"loanAmount":3000.0000,"loanBalance":3450.000000,"interestRate":1.15,"applicationDate":"2022-04-19T00:00:00","disbursmentDate":"2022-04-26T00:00:00","dueDate":"2022-04-25T00:00:00","defaulted":false,"approved":true,"customerID":40140676,"customer":null,"loansHistories":[{"histID":1012,"rePaidIn":300.0000,"repayementDateDate":"2022-04-05T00:00:00","noOfPayinyingIntrestOnly":1,"loanID":10},{"histID":1013,"rePaidIn":150.0000,"repayementDateDate":"2022-04-19T00:00:00","noOfPayinyingIntrestOnly":2,"loanID":10},{"histID":1014,"rePaidIn":300.0000,"repayementDateDate":"2022-04-11T00:00:00","noOfPayinyingIntrestOnly":3,"loanID":10},{"histID":1015,"rePaidIn":150.0000,"repayementDateDate":"2022-04-11T00:00:00","noOfPayinyingIntrestOnly":4,"loanID":10},{"histID":1016,"rePaidIn":300.0000,"repayementDateDate":"2022-04-06T00:00:00","noOfPayinyingIntrestOnly":5,"loanID":10},{"histID":1017,"rePaidIn":150.0000,"repayementDateDate":"2022-04-04T00:00:00","noOfPayinyingIntrestOnly":6,"loanID":10},{"histID":1018,"rePaidIn":300.0000,"repayementDateDate":"2022-04-05T00:00:00","noOfPayinyingIntrestOnly":7,"loanID":10},{"histID":1019,"rePaidIn":150.0000,"repayementDateDate":"2022-04-19T00:00:00","noOfPayinyingIntrestOnly":8,"loanID":10},{"histID":1020,"rePaidIn":150.0000,"repayementDateDate":"2022-04-02T00:00:00","noOfPayinyingIntrestOnly":9,"loanID":10},{"histID":1021,"rePaidIn":150.0000,"repayementDateDate":"2022-04-04T00:00:00","noOfPayinyingIntrestOnly":10,"loanID":10},{"histID":1022,"rePaidIn":100.0000,"repayementDateDate":"2022-04-06T00:00:00","noOfPayinyingIntrestOnly":12,"loanID":10},{"histID":1023,"rePaidIn":350.0000,"repayementDateDate":"2022-04-04T00:00:00","noOfPayinyingIntrestOnly":13,"loanID":10},{"histID":1024,"rePaidIn":100.0000,"repayementDateDate":"2022-04-12T00:00:00","noOfPayinyingIntrestOnly":14,"loanID":10},{"histID":1025,"rePaidIn":350.0000,"repayementDateDate":"2022-04-11T00:00:00","noOfPayinyingIntrestOnly":6,"loanID":10},{"histID":1026,"rePaidIn":100.0000,"repayementDateDate":"2022-04-20T00:00:00","noOfPayinyingIntrestOnly":14,"loanID":10},{"histID":1027,"rePaidIn":1000.0000,"repayementDateDate":"2022-04-12T00:00:00","noOfPayinyingIntrestOnly":16,"loanID":10},{"histID":1028,"rePaidIn":1000.0000,"repayementDateDate":"2022-04-04T00:00:00","noOfPayinyingIntrestOnly":17,"loanID":10},{"histID":1029,"rePaidIn":1000.0000,"repayementDateDate":"2022-04-04T00:00:00","noOfPayinyingIntrestOnly":18,"loanID":10}]},{"loanID":11,"loanAmount":1000.0000,"loanBalance":1150.000000,"interestRate":1.15,"applicationDate":"2022-04-26T00:00:00","disbursmentDate":"2022-04-25T00:00:00","dueDate":"2022-04-05T00:00:00","defaulted":false,"approved":true,"customerID":30290122,"customer":null,"loansHistories":[{"histID":1030,"rePaidIn":150.0000,"repayementDateDate":"2022-04-05T00:00:00","noOfPayinyingIntrestOnly":1,"loanID":11},{"histID":1031,"rePaidIn":150.0000,"repayementDateDate":"2022-04-12T00:00:00","noOfPayinyingIntrestOnly":5,"loanID":11}]},{"loanID":12,"loanAmount":1000.0000,"loanBalance":1150.000000,"interestRate":1.15,"applicationDate":"2022-04-24T00:00:00","disbursmentDate":"2022-04-24T00:00:00","dueDate":"2022-04-25T00:00:00","defaulted":false,"approved":true,"customerID":40140676,"customer":null,"loansHistories":[{"histID":1032,"rePaidIn":150.0000,"repayementDateDate":"2022-04-04T00:00:00","noOfPayinyingIntrestOnly":1,"loanID":12},{"histID":1033,"rePaidIn":150.0000,"repayementDateDate":"2022-03-28T00:00:00","noOfPayinyingIntrestOnly":3,"loanID":12}]},{"loanID":13,"loanAmount":2000.0000,"loanBalance":2300.000000,"interestRate":1.15,"applicationDate":"2022-04-24T00:00:00","disbursmentDate":"2022-04-25T00:00:00","dueDate":"2022-05-03T00:00:00","defaulted":false,"approved":true,"customerID":30290122,"customer":null,"loansHistories":[{"histID":1034,"rePaidIn":300.0000,"repayementDateDate":"2022-03-28T00:00:00","noOfPayinyingIntrestOnly":1,"loanID":13},{"histID":1035,"rePaidIn":300.0000,"repayementDateDate":"2022-04-12T00:00:00","noOfPayinyingIntrestOnly":9,"loanID":13}]},{"loanID":14,"loanAmount":1000.0000,"loanBalance":1150.000000,"interestRate":1.15,"applicationDate":"2022-04-25T00:00:00","disbursmentDate":"2022-04-06T00:00:00","dueDate":"2022-04-26T00:00:00","defaulted":false,"approved":true,"customerID":30290122,"customer":null,"loansHistories":[{"histID":1036,"rePaidIn":150.0000,"repayementDateDate":"2022-04-05T00:00:00","noOfPayinyingIntrestOnly":1,"loanID":14},{"histID":1037,"rePaidIn":1000.0000,"repayementDateDate":"2022-04-04T00:00:00","noOfPayinyingIntrestOnly":4,"loanID":14},{"histID":1038,"rePaidIn":150.0000,"repayementDateDate":"2022-04-18T00:00:00","noOfPayinyingIntrestOnly":4,"loanID":14},{"histID":1039,"rePaidIn":1000.0000,"repayementDateDate":"2022-04-11T00:00:00","noOfPayinyingIntrestOnly":5,"loanID":14},{"histID":1040,"rePaidIn":100.0000,"repayementDateDate":"2022-04-19T00:00:00","noOfPayinyingIntrestOnly":6,"loanID":14},{"histID":1041,"rePaidIn":50.0000,"repayementDateDate":"2022-04-04T00:00:00","noOfPayinyingIntrestOnly":7,"loanID":14},{"histID":1042,"rePaidIn":50.0000,"repayementDateDate":"2022-04-05T00:00:00","noOfPayinyingIntrestOnly":8,"loanID":14},{"histID":1043,"rePaidIn":50.0000,"repayementDateDate":"2022-04-06T00:00:00","noOfPayinyingIntrestOnly":8,"loanID":14},{"histID":1044,"rePaidIn":1000.0000,"repayementDateDate":"2022-03-28T00:00:00","noOfPayinyingIntrestOnly":89,"loanID":14}]},{"loanID":1014,"loanAmount":5000.0000,"loanBalance":5750.000000,"interestRate":1.15,"applicationDate":"2022-03-28T00:00:00","disbursmentDate":"2022-04-11T00:00:00","dueDate":"2022-04-12T00:00:00","defaulted":false,"approved":true,"customerID":40140676,"customer":null,"loansHistories":[{"histID":2035,"rePaidIn":750.0000,"repayementDateDate":"2022-04-11T00:00:00","noOfPayinyingIntrestOnly":1,"loanID":1014},{"histID":2036,"rePaidIn":1000.0000,"repayementDateDate":"2022-04-12T00:00:00","noOfPayinyingIntrestOnly":2,"loanID":1014},{"histID":2037,"rePaidIn":750.0000,"repayementDateDate":"2022-03-30T00:00:00","noOfPayinyingIntrestOnly":3,"loanID":1014}]}]
现在我想计算 loanHistories table 中的 rePaidIn 总和并在贷款 table 中显示 TotalRepaidIn 标题为 [NotMapped]：我尝试了以下 link .it seems close to answer my question but it does not 这是我的控制器
[HttpGet]
public async Task<ActionResult<IEnumerable<Loan>>> Getloans()
{
return await _context.loans.Include(lh => lh.loansHistories).ToListAsync();
}
任何解决方案将不胜感激。提前致谢
这是一个完整的工作演示：
型号：
public class Loan
{
[Key]
public int LoanID { get; set; }
[DataType(DataType.Currency)]
[Column(TypeName = "money")]
public decimal LoanAmount { get; set; }
[DataType(DataType.Currency)]
[Column(TypeName = "money")]
[Display(Name = "Loan Balance")]
private decimal _LoanBalance;
[Column(TypeName = "decimal(18,2)")]
public decimal LoanBalance
{
get
{
return LoanAmount * interestRate;
}
set { _LoanBalance = value; }
}
[Column(TypeName = "decimal(18,2)")]
[Display(Name = "Interest Rate")]
public decimal interestRate { get; set; }
//....
[Display(Name = "Approved")]
public bool Approved { get; set; }
//public ICollection<LoanComments> loancomments { get; set; }
public ICollection<LoansHistories> loansHistories { get; set; }
[NotMapped]
public decimal TotalRepaidIn { get; set; } //add this...
}
public class LoansHistories
{
[Key]
public int HistID { get; set; }
[DataType(DataType.Currency)]
[Column(TypeName = "money")]
[Display(Name = "Repaid Amount")]
public decimal RePaidIn { get; set; }
[DataType(DataType.Date)]
[DisplayFormat(DataFormatString = "{0:yyyy-MM-dd}", ApplyFormatInEditMode = true)]
[Display(Name = "Repayement Date")]
public DateTime RepayementDateDate { get; set; }
[Display(Name = "No of paying interest only")]
public int NoOfPayinyingIntrestOnly { get; set; }
public int LoanID { get; set; }
public Loan loan { get; set; }
}
控制器：
public async Task<ActionResult<IEnumerable<Loan>>> Getloans()
{
var data = await _context.loans.Include(lh => lh.loansHistories).Select(l=>new Loan()
{
TotalRepaidIn = l.loansHistories.Select(lh=>lh.RePaidIn).Sum(),
loansHistories = l.loansHistories,
ApplicationDate = l.ApplicationDate,
Defaulted=l.Defaulted,
DisbursmentDate= l.DisbursmentDate,
DueDate= l.DueDate,
LoanID=l.LoanID,
Approved=l.Approved,
interestRate=l.interestRate,
LoanAmount=l.LoanAmount
}).ToListAsync();
return data;
}
更新：
更好的方法是像下面这样更改模型：
using System.Linq; //import this namespace...
public class Loan
{
[Key]
public int LoanID { get; set; }
[DataType(DataType.Currency)]
[Column(TypeName = "money")]
public decimal LoanAmount { get; set; }
private decimal _TotalRepaidIn;
[NotMapped]
public decimal TotalRepaidIn
{
get { return loansHistories.Sum(sum => sum.RePaidIn); }
set { _TotalRepaidIn = value; }
}
//other properties
public ICollection<LoansHistories> loansHistories { get; set; } = new List<LoansHistories>();
}
控制器：
public async Task<ActionResult<IEnumerable<Loan>>> Getloans()
{
return await _context.loans.Include(lh => lh.loansHistories).ToListAsync();
}