[raelkun00]

I am having error if one of the fields in MS Database is empty and I will load it in textbox
Here is my code.

 Dim ObjCon As New dbConnect
        ObjCon.con.Open()
        Dim da As New OleDbDataAdapter '("SELECT * FROM customer", ObjCon.con)
        Dim dt As New DataTable
        Try
            Dim cmd = New OleDbCommand("Select * from tbl_Customer where cust_company='" & cboSearch.Text & "'", ObjCon.con)
            da = New OleDbDataAdapter(cmd)
            da.Fill(dt)
            txtCstID.Text = dt.Rows(0).Item(0)
            txtCstFName.Text = dt.Rows(0).Item(1)
            txtCstLName.Text = dt.Rows(0).Item(2)
            txtCstCompany.Text = dt.Rows(0).Item(3)
            txtCstAddress.Text = dt.Rows(0).Item(4)
            cboCstCity.Text = dt.Rows(0).Item(5)
            txtCstTel.Text = dt.Rows(0).Item(6)
            txtCstEmail.Text = dt.Rows(0).Item(7)
            txtCstWeb.Text = dt.Rows(0).Item(8)
            txtCstFax.Text = dt.Rows(0).Item(9)
            ObjCon.con.Close()
        Catch ex As Exception
            MessageBox.Show(ex.ToString)
        End Try

Here is the error I am getting

This post has been edited by raelkun00: 31 July 2013 - 11:11 AM

[ybadragon]

What is the error you are getting? At what line does it occur?

Also I would recommend that you use Parameterized queries in your OleDbCommand. like so

Dim cmd = New OleDbCommand("Select * from tbl_Customer where [email protected]", ObjCon.con)
cmd.Parameters.AddWithValue("@cboSearch", cboSearch.Text)
da = New OleDbDataAdapter(cmd)
.
.
.

This makes the SQL statements easier to read as well as helping against SQL Injection

This post has been edited by ybadragon: 31 July 2013 - 11:14 AM

[ybadragon]

Ok, we need to know the line that it is erroring on in the code you provided, from what it looks like you are trying to store a "Null" value into your textbox, which isn't allowed.

[andrewsw]

You haven't said which field it is but you might add the following to a number of the fields, to handle DBNull:

txtCstFName.Text = If(IsDBNull(dt.Rows(0).Item(1)), "", CStr(dt.Rows(0).Item(1)))

This post has been edited by andrewsw: 31 July 2013 - 11:21 AM

[raelkun00]

I get error if I store a null value from Database to textbox. I can get error from any fields if its null and I will store it in textbox.
Still have error.

 Dim ObjCon As New dbConnect
        ObjCon.con.Open()
        Dim da As New OleDbDataAdapter '("SELECT * FROM customer", ObjCon.con)
        Dim dt As New DataTable
        Try
            Dim cmd = New OleDbCommand("Select * from tbl_Customer where cust_firstname='" & cboSearch.Text & "'", ObjCon.con)
            da = New OleDbDataAdapter(cmd)
            da.Fill(dt)
            txtCstID.Text = dt.Rows(0).Item(0)
            txtCstFName.Text = If(IsDBNull(dt.Rows(0).Item(1)), "", CStr(dt.Rows(0).Item(1)))
            txtCstLName.Text = dt.Rows(0).Item(2)
            txtCstCompany.Text = dt.Rows(0).Item(3)
            txtCstAddress.Text = dt.Rows(0).Item(4)
            cboCstCity.Text = dt.Rows(0).Item(5)
            txtCstTel.Text = dt.Rows(0).Item(6)
            txtCstEmail.Text = dt.Rows(0).Item(7)
            txtCstWeb.Text = dt.Rows(0).Item(8)
            txtCstFax.Text = dt.Rows(0).Item(9)

            ObjCon.con.Close()
        Catch ex As Exception
            MessageBox.Show(ex.ToString)
        End Try

[ybadragon]

You need to tell us what line in the code you've provided the error occurs on. Put a breakpoint on da.Fill(dt) and step through the code to figure out where the error occurs.

[raelkun00]

Thank you, Your suggestion was right. I just put it in a wrong method.