รบกวนดูวิธีการ check ค่า gridview โดยการวนลูปบรรทัดแรกถึงบรรทัดสุด้ายนำไปเช็คกับตารางใน database ถ้าตรงกันให้แจ้งซ้ำด้วยครับ

foreach(DataGridView row in dgv2.Rows)
              {
              for(int i = 0; i < dgv2.Columns.Count; i++)
              {        
                  cmd1 = new SqlCommand("select * from Cometowork1 where Empid=@Empid and Date=@Date", con);
                  cmd1.Parameters.AddWithValue("@Empid", Convert.ToString(dgv2.Rows[i].Cells[0].Value ?? DBNull.Value));
                  cmd1.Parameters.AddWithValue("@Date", dtp1.Text);   
                  SqlDataAdapter da1 = new SqlDataAdapter(cmd1);
                  da1.Fill(ds1);
                 int i = ds1.Tables[0].Rows.Count; 
                  if (i > 0)
                  {
                      DialogResult result = MessageBox.Show("ข้อมูลซ้ำโปรดตรวจสอบ", "ERROR!", MessageBoxButtons.OK, MessageBoxIcon.Error);
                      ds1.Clear();
                  }   
                  else

USE [YourDB]
GO
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
 
IF OBJECT_ID ( '[dbo].[msrFormPerm_usp01]', 'P' ) IS NOT NULL
    DROP PROCEDURE [dbo].[msrFormPerm_usp01]
GO
 
CREATE PROCEDURE [dbo].[msrFormPerm_usp01]
(
 @PageID AS int = 0,
 @RoleIDc AS nvarchar(MAX) = '',
 @UserID AS int = 0
) 
AS
BEGIN
 SET NOCOUNT ON ;
  
 DECLARE @strSQL AS nvarchar(MAX) ='' ;
     
   SET @strSQL = 'SELECT c.ACL,
                   0 As Flag,
                   0 As Priority
                   FROM msrFormPerm c WHERE c.PageID ='
                   + CAST(@PageID AS varchar)
                   + ' '
                   + 'AND (c.RoleID = 0 OR c.RoleID IS NULL) AND c.UserID ='
                   + ' '
                   + CAST(@UserID AS varchar)
                   + ' '
                   + 'AND c.IsActive = 1'
                   + ' '
                   + 'UNION ALL'
                   + ' '
                   + 'SELECT a.ACL,
                   1 As Flag,
                   b.Priority
                   FROM msrFormPerm a INNER JOIN msrRoles b ON a.RoleID = b.RoleID
                   WHERE a.PageID ='
                   + ' '
                   + CAST(@PageID AS varchar)
                   + ' '
                   + 'AND a.RoleID IN('
                   + @RoleIDc
                   + ') '
                   + 'AND (a.UserID = 0 OR a.UserID IS NULL) AND a.IsActive = 1 AND b.IsActive = 1' ;
                        
    EXEC sp_executesql @strSQL ;
     
END
GO

-- =============================================
-- Author:  Herudoy
-- Create date: 17 มิถุนายน พ.ศ. 2553
-- Description: SQLServer 2008 Express
-- (การผ่านค่า String Array ให้กับ Stored Procedure)
-- =============================================
DROP PROCEDURE IF EXISTS wsdb.msrFormPerm_usp01;
 
CREATE PROCEDURE wsdb.`msrFormPerm_usp01`(IN `PageID` int, IN `RoleIDc` varchar(20000), IN `UserID` int)
    READS SQL DATA
 
BEGIN
 SET @strSQL = CONCAT('SELECT c.ACL,
                       0 As Flag,
                       0 As Priority
                       FROM msrFormPerm c WHERE c.PageID ='
                       , PageID
                       , ' '
                       , 'AND (c.RoleID = 0 OR c.RoleID IS NULL) AND c.UserID ='
                       , ' '
                       , UserID
                       , ' '
                       , 'AND c.IsActive = 1'
                       , ' '
                       , 'UNION ALL'
                       , ' '
                       , 'SELECT a.ACL,
                       1 As Flag,
                       b.Priority
                       FROM msrFormPerm a INNER JOIN msrRoles b ON a.RoleID = b.RoleID
                       WHERE a.PageID ='
                       , ' '
                       , PageID
                       , ' '
                       , 'AND a.RoleID IN('
                       , RoleIDc
                       , ') '
                       , 'AND (a.UserID = 0 OR a.UserID IS NULL) AND a.IsActive = 1 AND b.IsActive = 1') ;
                     
   PREPARE stmt FROM @strSQL ;
   EXECUTE stmt ;
   DEALLOCATE PREPARE stmt ;
   
END;

function doAjax() {
    $.ajax({
        url: ajaxurl,
        type: 'POST',
        data: {
            stuff: "here"
        },
        success: function (data) {
            //wacky nested anonymous callbacks go here
            var something_but_not_really = data;
        },
        error: function (jqXHR, textStatus, errorThrown) {
            // Empty most of the time...
        }
    });

    return something_but_not_really
}


async function doAjax(args) {
    const result = await $.ajax({
        url: ajaxurl,
        type: 'POST',
        data: args
    });

    return result;
}


async function doAjax(args) {
    let result;

    try {
        result = await $.ajax({
            url: ajaxurl,
            type: 'POST',
            data: args
        });

        return result;
    } catch (error) {
        console.error(error);
    }
}

//Method 1
const stuff = await doAjax();

//Method 2
doAjax().then((data) => doStuff(data))