Dear Experts,
I have created a user control (use a combobox only)
Code is as follows:
------------------------
Public Class Company
Public Event ComID(ByVal Com As Object)
Private Sub ComboBox1_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmbCompany.SelectedIndexChanged
RaiseEvent ComID(cmbCompany.SelectedValue)
End Sub
Private Sub CallCom(ByVal SQL As String)
Try
Dim ds As DataSet = New DataSet
Dim da As New SqlClient.SqlDataAdapter(SQL, Cn)
da.SelectCommand.CommandType = CommandType.Text
da.Fill(ds, "ComID")
cmbCompany.DataSource = ds.Tables("ComID")
cmbCompany.DisplayMember = "Name"
cmbCompany.ValueMember = "CompanyCode"
Catch exSQL As SqlClient.SqlException
MessageBox.Show(exSQL.Message())
Finally

End Try
End Sub
Private Sub Company_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Call CallCom("select CompanyCode,Name from MtCM where del='0' order by CompanyCode")
End Sub
End Class

Problem
------------
When I am dragging control on form it is showing error (snapshot attached).

As it is showing connection string initializing error: I am providing below connection string for review:

Module Module1
Public Cn As New System.Data.SqlClient.SqlConnection

Sub main()
Try
'Cn = New System.Data.SqlClient.SqlConnection
Cn.ConnectionString = "password=jazzciti;Persist Security Info=True;User ID=sa;Initial Catalog=OILDB;Data Source=Mehram\SQLExpress"
Cn.Open()
If Cn.State = ConnectionState.Open Then
Application.Run(New frmUser)
End If
Catch exsql As SqlClient.SqlException
MessageBox.Show(exsql.Message())
Finally
Cn.Dispose()
End Try
End Sub
End Module


Please help
IM

Hi Iqbal,

From my experience, the root cause of your issue is that some code about database is executed in design-time. We can only execute code about database in runtime.

To solve this issue, we need to check the DesignMode property to ignore the code about database in design-time. This is an example:

    Private Sub Company_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        If Not DesignMode Then
            'Execute code only in runtime.
            Call CallCom("select CompanyCode,Name from MtCM where del='0' order by CompanyCode")
        End If
    End Sub

Let me know if this does not help.
Aland Li

Hi Iqbal,

From my experience, the root cause of your issue is that some code about database is executed in design-time. We can only execute code about database in runtime.

To solve this issue, we need to check the DesignMode property to ignore the code about database in design-time. This is an example:

    Private Sub Company_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        If Not DesignMode Then
            'Execute code only in runtime.
            Call CallCom("select CompanyCode,Name from MtCM where del='0' order by CompanyCode")
        End If
    End Sub

Let me know if this does not help.
Aland Li

Hi Iqbal,

From my experience, the root cause of your issue is that some code about database is executed in design-time. We can only execute code about database in runtime.

To solve this issue, we need to check the DesignMode property to ignore the code about database in design-time. This is an example:

    Private Sub Company_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

        If Not DesignMode Then

            'Execute code only in runtime.

            Call CallCom("select CompanyCode,Name from MtCM where del='0' order by CompanyCode")

        End If

    End Sub

Let me know if this does not help.
Aland Li

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