如何使用 sql Bulkcopy 在 table 中插入 datagridview 行
how to use sql Bulkcopy to insert datagridview rows in table
我想将 datagridview 行插入 sql 服务器 tables ...
现在使用此代码在 table 中插入来自 DataGridView 的行值:
private DataTable GetDataTableFromDGV(DataGridView dgv)
{
var dt = new DataTable();
foreach (DataGridViewColumn column in dgv.Columns)
{
if (column.Visible)
{
dt.Columns.Add();
}
}
object[] cellValues = new object[dgv.Columns.Count];
foreach (DataGridViewRow row in dgv.Rows)
{
for (int i = 0; i < row.Cells.Count; i++)
{
cellValues[i] = row.Cells[i].Value;
}
dt.Rows.Add(cellValues);
}
return dt;
}
private void InsertDTtoDB(string ConnectionString, string TableName, DataGridView DGV)
{
DataTable dt = new DataTable();
dt = GetDataTableFromDGV(DGV);
using (SqlConnection cn = new SqlConnection(ConnectionString))
{
cn.Open();
using (SqlBulkCopy copy = new SqlBulkCopy(cn))
{
copy.ColumnMappings.Add(0, 1);
copy.ColumnMappings.Add(1, 2);
copy.ColumnMappings.Add(2, 3);
copy.ColumnMappings.Add(3, 4);
copy.ColumnMappings.Add(4, 5);
copy.DestinationTableName = TableName;
copy.WriteToServer(dt);
}
}
}
但是插入数据时遇到问题:
来自 datatgridview 的空行(启用添加行)存储在最后 tables 行中!
请注意图片帮助:
首先,一些可能有助于您更好地理解用 C# 编写代码的一般观察:
// this line is declaring a new variable named 'dt'
// and assigning it an instance of a new DataTable
DataTable dt = new DataTable();
// this line is immediately overwriting the new DataTable
// assigned to 'dt' with the DataTable returned from 'GetDataTableFromDGV'
dt = GetDataTableFromDGV(DGV);
上面应该写成声明变量然后赋值:
DataTable dt = GetDataTableFromDGV(DBV);
来自 GetDataTableFromDGV
的以下内容将仅在列可见时向 DataTable 添加列:
foreach (DataGridViewColumn column in dgv.Columns)
{
if (column.Visible)
{
dt.Columns.Add();
}
}
然后在 InsertDTtoDB
中使用上面的 DataTable 结果,这显然需要在预定义的序号位置设置一定数量的列:
copy.ColumnMappings.Add(0, 1);
// etc...
上面在 GetDataTableFromDGV
中创建的 DataTable 之间创建了一个非常脆弱的关系,它要求 Column 可见,然后在 InsertDTtoDB
中使用。
与其在 DataTable 和 SqlBulkCopy.ColumnMappings 之间使用脆弱的序号关系,不如使用字段名称创建 DataTable,然后映射到 SqlBulkCopy。 `GetDataTableFromDGV'中的foreach,则变为:
// assumes the columns in the DataGridView are named as follows:
var columns = new[] {"Id", "Invoice_Id", "Software_Id", "Price", "Quantity", "Sum" }
var dt = new DataTable();
foreach (DataGridViewColumn column in dgv.Columns)
{
// note: this is case-sensitive
if (columns.Contains(column.Name))
{
dt.Columns.Add();
}
}
然后 InsertDTtoDB
中的 ColumnMappings 变为:
copy.ColumnMappings.Add("Invoice_Id", "DestinationCol1");
copy.ColumnMappings.Add("Software_Id", "DestinationCol2");
// etc...
将行添加到 GetDataTableFromDGV
中的 DataTable 时,cellValues
变量在 foreach 循环外声明,但值在内部 for 循环中不断被覆盖。不是将对象数组添加到 DataTable,而是使用实际的列名称构建 DataRow 并将新的 DataRow 添加到 DataTable。
考虑到上述情况,GetDataTableFromDGV
方法就变成了:
private DataTable GetDataTableFromDGV(DataGridView dgv)
{
// use your actual columns names instead of Col1, Col2, etc...
var columns = new[] {"Invoice_Id", "Software_Id", "Price", "Quantity", "Sum" }
var dt = new DataTable();
foreach (DataGridViewColumn column in dgv.Columns)
{
if (columns.Contains(column.Name))
{
dt.Columns.Add();
}
}
foreach (DataGridViewRow row in dgv.Rows)
{
DataRow newRow = dt.NewRow();
foreach (string columnName in columns)
{
newRow[columnName] = row.Cells[columnName].Value
}
dt.Rows.Add(newRow);
}
return dt;
}
然后 InsertDTtoDB
方法变为:
private void InsertDTtoDB(string ConnectionString, string TableName, DataGridView DGV)
{
DataTable dt = GetDataTableFromDGV(DGV);
using (SqlConnection cn = new SqlConnection(ConnectionString))
{
cn.Open();
using (SqlBulkCopy copy = new SqlBulkCopy(cn))
{
// update the "DestinationCol[x]" values to the destination column names
copy.ColumnMappings.Add("Invoice_Id", "DestinationCol1");
copy.ColumnMappings.Add("Software_Id", "DestinationCol2");
copy.ColumnMappings.Add("Price", "DestinationCol3");
copy.ColumnMappings.Add("Quantity", "DestinationCol4");
copy.ColumnMappings.Add("Sum", "DestinationCol5");
copy.DestinationTableName = TableName;
copy.WriteToServer(dt);
}
}
}
为了回答您关于为什么将空行添加到数据库的问题,我怀疑这是因为 DataGridView 中存在空值。假设是这种情况,则将 DataGridView 中的空值排除在添加到 DataTable 之外。我会关闭其中一个关键列,例如 "Invoice_Id";然后 GetDataTableFromDGV
方法变为:
private DataTable GetDataTableFromDGV(DataGridView dgv)
{
// assumes the columns in the DataGridView are named as follows:
var columns = new[] {"Invoice_Id", "Software_Id", "Price", "Quantity", "Sum" }
var dt = new DataTable();
foreach (DataGridViewColumn column in dgv.Columns)
{
if (columns.Contains(column.Name))
{
dt.Columns.Add();
}
}
foreach (DataGridViewRow row in dgv.Rows)
{
// check if the row has a null "Invoice_Id" and exclude
if(row.Cells["Invoice_Id"] == null
{
continue;
}
DataRow newRow = dt.NewRow();
foreach (string columnName in columns)
{
newRow[columnName] = row.Cells[columnName].Value
}
dt.Rows.Add(newRow);
}
return dt;
}
我想将 datagridview 行插入 sql 服务器 tables ... 现在使用此代码在 table 中插入来自 DataGridView 的行值:
private DataTable GetDataTableFromDGV(DataGridView dgv)
{
var dt = new DataTable();
foreach (DataGridViewColumn column in dgv.Columns)
{
if (column.Visible)
{
dt.Columns.Add();
}
}
object[] cellValues = new object[dgv.Columns.Count];
foreach (DataGridViewRow row in dgv.Rows)
{
for (int i = 0; i < row.Cells.Count; i++)
{
cellValues[i] = row.Cells[i].Value;
}
dt.Rows.Add(cellValues);
}
return dt;
}
private void InsertDTtoDB(string ConnectionString, string TableName, DataGridView DGV)
{
DataTable dt = new DataTable();
dt = GetDataTableFromDGV(DGV);
using (SqlConnection cn = new SqlConnection(ConnectionString))
{
cn.Open();
using (SqlBulkCopy copy = new SqlBulkCopy(cn))
{
copy.ColumnMappings.Add(0, 1);
copy.ColumnMappings.Add(1, 2);
copy.ColumnMappings.Add(2, 3);
copy.ColumnMappings.Add(3, 4);
copy.ColumnMappings.Add(4, 5);
copy.DestinationTableName = TableName;
copy.WriteToServer(dt);
}
}
}
但是插入数据时遇到问题: 来自 datatgridview 的空行(启用添加行)存储在最后 tables 行中! 请注意图片帮助:
首先,一些可能有助于您更好地理解用 C# 编写代码的一般观察:
// this line is declaring a new variable named 'dt'
// and assigning it an instance of a new DataTable
DataTable dt = new DataTable();
// this line is immediately overwriting the new DataTable
// assigned to 'dt' with the DataTable returned from 'GetDataTableFromDGV'
dt = GetDataTableFromDGV(DGV);
上面应该写成声明变量然后赋值:
DataTable dt = GetDataTableFromDGV(DBV);
来自 GetDataTableFromDGV
的以下内容将仅在列可见时向 DataTable 添加列:
foreach (DataGridViewColumn column in dgv.Columns)
{
if (column.Visible)
{
dt.Columns.Add();
}
}
然后在 InsertDTtoDB
中使用上面的 DataTable 结果,这显然需要在预定义的序号位置设置一定数量的列:
copy.ColumnMappings.Add(0, 1);
// etc...
上面在 GetDataTableFromDGV
中创建的 DataTable 之间创建了一个非常脆弱的关系,它要求 Column 可见,然后在 InsertDTtoDB
中使用。
与其在 DataTable 和 SqlBulkCopy.ColumnMappings 之间使用脆弱的序号关系,不如使用字段名称创建 DataTable,然后映射到 SqlBulkCopy。 `GetDataTableFromDGV'中的foreach,则变为:
// assumes the columns in the DataGridView are named as follows:
var columns = new[] {"Id", "Invoice_Id", "Software_Id", "Price", "Quantity", "Sum" }
var dt = new DataTable();
foreach (DataGridViewColumn column in dgv.Columns)
{
// note: this is case-sensitive
if (columns.Contains(column.Name))
{
dt.Columns.Add();
}
}
然后 InsertDTtoDB
中的 ColumnMappings 变为:
copy.ColumnMappings.Add("Invoice_Id", "DestinationCol1");
copy.ColumnMappings.Add("Software_Id", "DestinationCol2");
// etc...
将行添加到 GetDataTableFromDGV
中的 DataTable 时,cellValues
变量在 foreach 循环外声明,但值在内部 for 循环中不断被覆盖。不是将对象数组添加到 DataTable,而是使用实际的列名称构建 DataRow 并将新的 DataRow 添加到 DataTable。
考虑到上述情况,GetDataTableFromDGV
方法就变成了:
private DataTable GetDataTableFromDGV(DataGridView dgv)
{
// use your actual columns names instead of Col1, Col2, etc...
var columns = new[] {"Invoice_Id", "Software_Id", "Price", "Quantity", "Sum" }
var dt = new DataTable();
foreach (DataGridViewColumn column in dgv.Columns)
{
if (columns.Contains(column.Name))
{
dt.Columns.Add();
}
}
foreach (DataGridViewRow row in dgv.Rows)
{
DataRow newRow = dt.NewRow();
foreach (string columnName in columns)
{
newRow[columnName] = row.Cells[columnName].Value
}
dt.Rows.Add(newRow);
}
return dt;
}
然后 InsertDTtoDB
方法变为:
private void InsertDTtoDB(string ConnectionString, string TableName, DataGridView DGV)
{
DataTable dt = GetDataTableFromDGV(DGV);
using (SqlConnection cn = new SqlConnection(ConnectionString))
{
cn.Open();
using (SqlBulkCopy copy = new SqlBulkCopy(cn))
{
// update the "DestinationCol[x]" values to the destination column names
copy.ColumnMappings.Add("Invoice_Id", "DestinationCol1");
copy.ColumnMappings.Add("Software_Id", "DestinationCol2");
copy.ColumnMappings.Add("Price", "DestinationCol3");
copy.ColumnMappings.Add("Quantity", "DestinationCol4");
copy.ColumnMappings.Add("Sum", "DestinationCol5");
copy.DestinationTableName = TableName;
copy.WriteToServer(dt);
}
}
}
为了回答您关于为什么将空行添加到数据库的问题,我怀疑这是因为 DataGridView 中存在空值。假设是这种情况,则将 DataGridView 中的空值排除在添加到 DataTable 之外。我会关闭其中一个关键列,例如 "Invoice_Id";然后 GetDataTableFromDGV
方法变为:
private DataTable GetDataTableFromDGV(DataGridView dgv)
{
// assumes the columns in the DataGridView are named as follows:
var columns = new[] {"Invoice_Id", "Software_Id", "Price", "Quantity", "Sum" }
var dt = new DataTable();
foreach (DataGridViewColumn column in dgv.Columns)
{
if (columns.Contains(column.Name))
{
dt.Columns.Add();
}
}
foreach (DataGridViewRow row in dgv.Rows)
{
// check if the row has a null "Invoice_Id" and exclude
if(row.Cells["Invoice_Id"] == null
{
continue;
}
DataRow newRow = dt.NewRow();
foreach (string columnName in columns)
{
newRow[columnName] = row.Cells[columnName].Value
}
dt.Rows.Add(newRow);
}
return dt;
}