从 C# 中的现有数据库结构自动填充 DataTable

Question

我有一个 WinForm，它要求在文本框中插入一封电子邮件，在单击搜索按钮后，sql 查询将在 table 中搜索记录并将结果显示在数据网格视图。这里是搜索按钮的代码

private void RegUnregSearchButton_Click(object sender, EventArgs e)
    {
        var dataAccess = new DataAccess();
        var output = dataAccess.BindGrid(EmailTextBox.Text);

        DataGridView1.DataSource = output;
    }

BindGrid 的目的是根据查询结果自动填充数据的列和行table，但现在我正在手动执行，因为我不明白如何检索来自 Dapper 结果的列。

public class DataAccess
{
    public DataTable BindGrid(string param)
    {
        DataTable dataTable = new DataTable();
        
        //Helper.connString("SqlConnectionString") will take the connection string from an app.config and return the value. Connection works.
        using (IDbConnection connection = new System.Data.SqlClient.SqlConnection(Helper.connString("SqlConnectionString")))
        {
            var result = connection.Query("SELECT Company, Email, Role, Id, Status from table WHERE Email = '{param}'").ToList();
                    
            RegUnregUser user = new RegUnregUser();
            user.company = result.Select(x => x.Company).FirstOrDefault();
            user.email = result.Select(x => x.Email).FirstOrDefault();
            user.role = result.Select(x => x.Role).FirstOrDefault();
            user.id = result.Select(x => x.Id).FirstOrDefault();
            user.status = result.Select(x => x.Status).FirstOrDefault();

            dataTable.Columns.Add("Company");
            dataTable.Columns.Add("Email");
            dataTable.Columns.Add("Role");
            dataTable.Columns.Add("Id");
            dataTable.Columns.Add("Status");
            dataTable.Rows.Add(user.company, user.email, user.role, user.id, user.status);
            
            return dataTable;
        }
    }
}

RegUnregUser class:

public class RegUnregUser
{
    public string company { get; set; }
    public string email { get; set; }
    public string role { get; set; }
    public object id { get; set; }
    public string status { get; set; }
}

Answer 1

Dapper 用于映射到自定义对象，不适用于 DataTables。话虽这么说，你应该可以这样做：

public class DataAccess
{
    public DataTable BindGrid(string param)
    {
        //Helper.connString("SqlConnectionString") will take the connection string from an app.config and return the value. Connection works.
        using (IDbConnection connection = new System.Data.SqlClient.SqlConnection(Helper.connString("SqlConnectionString")))
        {
            var reader = connection.ExecuteReader("SELECT Company, Email, Role, Id, Status from table WHERE Email = @Email", 
               new {Email=param});
            return new DataTable().Load(reader);
        }
    }
}

注意我正在使用参数化查询。您的代码容易受到 SQL 注入攻击。

从 C# 中的现有数据库结构自动填充 DataTable

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