Alert in asp.net on code behind page with vb.net

 Protected Sub btnEnter_Click( ) Handles btnSubmit.Click

      Dim str As String
    str = "select field1 , field2 from table_name where field1=" & Trim(txtval.Text) & " and field2='somevalue' and tdate='"

& txtdate.SelectedDate & "'"
            Dim datareader_rad As SqlClient.SqlDataReader
            Dim sqlcommandname As New SqlCommand(str, con)
            con.Open()

           datareader_rad= sqlcommandname.ExecuteReader

            If datareader_rad .Read Then
                Try
     Response.Write("<script language='javascript'>alert('already value is  there in list.');</script>")
                Catch ex As Exception
                Finally

                    con.Close()

                End Try
            Else
                con.Close()
                dr.Close()

                Try
                    cmd = New SqlCommand("stoted_procedure_name", con)
                    cmd.CommandType = CommandType.StoredProcedure
                    cmd.Parameters.AddWithValue("@field1", Trim(txt1.Text))
                    cmd.Parameters.AddWithValue("@tablefield2", Trim(txt2.Text))
                    cmd.Parameters.AddWithValue("@time", Trim(txttime.Text))
                       Catch ex As Exception
                End Try
            End If
        End Sub
What  i did here just took one datareader and stored value ,  means stored field all value into datareader then checked using datareader_rad .read it shows if value already present in datareader then will show alert box that "already value is  entered".

     Response.Write("<script language='javascript'>alert('already value is  entered.');</script>")
by this code we can learn about javascript in  code behind  page in asp.net using vb.net

Share This