Question

我有使用SqlCommand在C＃中删除一行的代码。但是我想删除多行。谁能帮我这个？我是C＃的新手。

这是我的代码-请帮助。预先谢谢你。

foreach (DataGridViewRow dr in dataGrid1.SelectedRows)
            {
                SqlConnection con = new SqlConnection();
                con.ConnectionString = @"Data Source=DDBULK10\SQLEXPRESS;Initial Catalog=MasterList; Integrated Security = True";
                if (dr.Index > 0)
                {
                    int selectedIndex = dataGrid1.SelectedRows[0].Index;

                    int rowID = int.Parse(dataGrid1[0, selectedIndex].Value.ToString());
                    string sql = "DELETE FROM ActiveUser WHERE EmpId = @EmpId";

                    SqlCommand deleteRecord = new SqlCommand();
                    deleteRecord.Connection = con;
                    deleteRecord.CommandType = CommandType.Text;
                    deleteRecord.CommandText = sql;

                    SqlParameter RowParameter = new SqlParameter();
                    RowParameter.ParameterName = "@EmpId";
                    RowParameter.SqlDbType = SqlDbType.Int;
                    RowParameter.IsNullable = false;
                    RowParameter.Value = rowID;

                    deleteRecord.Parameters.Add(RowParameter);

                    deleteRecord.Connection.Open();

                    deleteRecord.ExecuteNonQuery();

                    //deleteRecord.Connection.Close();

                    MessageBox.Show("Record Successfully Deleted");

                    SqlDataAdapter sda = new SqlDataAdapter("select * from ActiveUser", con);
                    DataTable dt = new DataTable();
                    sda.Fill(dt);
                    dataGrid1.DataSource = dt;
                }

                else if (dialogResult == DialogResult.No)
                {
                    this.Refresh();
                }
            }

Answer 1

您可以建立一个逗号分隔的用户ID列表，例如-

string strUserIds = string.Empty();
for(int i=0; i<dataGrid.Count;i++)
{
  strUserIds = strUserIds +","+ dataGrid.SelectedRows[0].Cells[0].Value;
}
--Remove last unwanted comma from strUserIds 
then execute sql query as "DELETE FROM EmployeeTbl WHERE  UserID in (" + strUserIds + ")"

这将从表中删除多个记录。

Answer 2

只需对您的编码进行一些更改！

删除所有选定的行

从ActiveUser运行您的选择*

public void deldata（） { foreach（dataGrid1.SelectedRows中的DataGridViewRow dr） { SqlConnection con =新的SqlConnection（）; con.ConnectionString = @“数据源= DDBULK10 \ SQLEXPRESS;初始目录= MasterList；集成安全性= True”; 如果（dr.Index> 0） { int selectedIndex = dataGrid1.SelectedRows [0] .Index;

            int rowID = int.Parse(dataGrid1[0, selectedIndex].Value.ToString());
            string sql = "DELETE FROM ActiveUser WHERE EmpId = @EmpId";

            SqlCommand deleteRecord = new SqlCommand();
            deleteRecord.Connection = con;
            deleteRecord.CommandType = CommandType.Text;
            deleteRecord.CommandText = sql;

            SqlParameter RowParameter = new SqlParameter();
            RowParameter.ParameterName = "@EmpId";
            RowParameter.SqlDbType = SqlDbType.Int;
            RowParameter.IsNullable = false;
            RowParameter.Value = rowID;

            deleteRecord.Parameters.Add(RowParameter);

            deleteRecord.Connection.Open();

            deleteRecord.ExecuteNonQuery();

            //deleteRecord.Connection.Close();

            MessageBox.Show("Record Successfully Deleted");


        }

        else if (dialogResult == DialogResult.No)
        {
            this.Refresh();
        }
    }
}
public void showdata()
{
    SqlDataAdapter sda = new SqlDataAdapter("select * from ActiveUser", con);
    DataTable dt = new DataTable();
    sda.Fill(dt);
    dataGrid1.DataSource = dt;
}

Answer 3

您可以使用类似这样的东西；我没有测试代码，但是如果您创建所需的参数，它应该可以工作，在运行代码之前，您必须先创建一个type table, please see the link for details。

 using (connection)
        {
            string sql ="Delete from YourTable t join @yourTypeTable i on t.id = i.Id:";

            SqlCommand deleteCommand = new SqlCommand(sql, connection);
            SqlParameter tvpParam = deleteCommand.Parameters.AddWithValue("@yourTypeTable", yourIdList);
            tvpParam.SqlDbType = SqlDbType.Structured;
            tvpParam.TypeName = "dbo.yourTypeTable";

            deleteCommand.ExecuteNonQuery();
        }

如何使用SQL查询在C＃中删除多行？

3 个答案: