首页 > 解决方案 > 在网格视图中,我的行没有更新也没有删除

问题描述

我有一个网格视图,我想在其中应用 CRUD 操作。当我点击更新按钮时,它说:

System.NullReferenceException:对象引用未设置为 new_OCRS.Admin.gvReportCrime_RowUpdating(Object sender, GridViewUpdateEventArgs e) 处的对象实例"

当我单击删除按钮时,它不会显示任何错误,但不会删除值。

这是我的代码

 protected void gvReportCrime_RowUpdating(object sender, GridViewUpdateEventArgs e)
 {
    try
    {

        using (MySqlConnection con = new MySqlConnection(connectionString))
        {
            con.Open();
            string query = "UPDATE reportcrime SET Name=@Name,Phone1=@Phone1,Phone1,Phone2=Phone2,Email=@Email,Gender=@Gender,City=@City,Address=@Address,CrimeType=@CrimeType,CrimeDetail=@CrimeDetail WHERE CNIC = @CNIC";
            MySqlCommand mscmd = new MySqlCommand(query, con);
            mscmd.Parameters.AddWithValue("@Name", (gvReportCrime.Rows[e.RowIndex].FindControl("txtName") as TextBox).Text.Trim());
            mscmd.Parameters.AddWithValue("@ContactNo.1", (gvReportCrime.Rows[e.RowIndex].FindControl("txtPhone1") as TextBox).Text.Trim());
            mscmd.Parameters.AddWithValue("@ContactNo.2", (gvReportCrime.Rows[e.RowIndex].FindControl("txtPhone2") as TextBox).Text.Trim());
            mscmd.Parameters.AddWithValue("@EmailAddress", (gvReportCrime.Rows[e.RowIndex].FindControl("txtEmail") as TextBox).Text.Trim());
            mscmd.Parameters.AddWithValue("@Gender", (gvReportCrime.Rows[e.RowIndex].FindControl("txtGender") as TextBox).Text.Trim());
            mscmd.Parameters.AddWithValue("@CityName", (gvReportCrime.Rows[e.RowIndex].FindControl("txtCity") as TextBox).Text.Trim());
            mscmd.Parameters.AddWithValue("@PostalAddress", (gvReportCrime.Rows[e.RowIndex].FindControl("txtAddress") as TextBox).Text.Trim());
            mscmd.Parameters.AddWithValue("@CrimeType", (gvReportCrime.Rows[e.RowIndex].FindControl("txtCrimeType") as TextBox).Text.Trim());
            mscmd.Parameters.AddWithValue("@CrimeDetail", (gvReportCrime.Rows[e.RowIndex].FindControl("txtCrimeDetail") as TextBox).Text.Trim());
            mscmd.Parameters.AddWithValue("@CNICNO",Convert.ToString(gvReportCrime.DataKeys[e.RowIndex].Value.ToString()));
            mscmd.ExecuteNonQuery();
            gvReportCrime.EditIndex = -1;
            BindData();

        }
    }

    catch (Exception ex)
    {
            Response.Write("" + ex);
    }

 }

 protected void gvReportCrime_RowDeleting(object sender, GridViewDeleteEventArgs e)
    {
        try
        {

            using (MySqlConnection con = new MySqlConnection(connectionString))
            {
                con.Open();
                string query = "DELETE FROM reportcrime SET WHERE CNIC = @CNIC";
                MySqlCommand mscmd = new MySqlCommand(query, con);
                mscmd.Parameters.AddWithValue("@CNIC", Convert.ToString(gvReportCrime.DataKeys[e.RowIndex].Value.ToString()));
                mscmd.ExecuteNonQuery();
                BindData();

            }
        }
        catch (Exception ex)
        {
            Response.Write("" + ex);
        }
    }

标签: c#mysqlasp.net

解决方案


您的 AddWithValue 参数与您的更新查询不匹配。例如,您有以下

mscmd.Parameters.AddWithValue("@ContactNo.1",...)

但是您的更新语句中缺少@ContactNo.1。同样还有其他人。你需要解决这个问题。


推荐阅读