TextBox issue when binded to datatable

[vbtest5]

Hi,

We have an entry form that is binded to the datatable. There is an amount field. On this amount text box, when we delete the previous value and press tab key to go to next text box, the old value is displayed again in the text box? Why does this happen?

Regards,
Varsha

 

[SHelton]

This is the binding manager doing a bit of exception handling for you. The column you are binding the textbox to needs a numeric value, but you are passing it an empty string when you tab out of it. You can make the value equal zero when an empty string is entered by using the Parse event:

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

        Dim dt As New DataTable

        dt.Columns.Add(New DataColumn("Int", GetType(Int32)))

        For i As Int32 = 1 To 10

            Dim dr As DataRow = dt.NewRow()

            dr(0) = i

            dt.Rows.Add(dr)

        Next

        Dim b As Binding = New Binding("Text", dt, "Int")

        AddHandler b.Parse, AddressOf TextBox1_Parse

        TextBox1.DataBindings.Add(b)

End Sub

Private Sub TextBox1_Parse(ByVal sender As Object, ByVal e As ConvertEventArgs)

        If e.Value.ToString = "" Then e.Value = 0

End Sub

 

[vbtest5]

hi SHelton,

Thanks for your reply. I also find that even if I type 1 or 2 numeric key values and press the tab key, I again get back the same old value. Why?

Regards,
Varsha

 

[SHelton]

Are you sure the data column is not set to ReadOnly ? Otherwise, I cannot see why the value is changing back - I cannot reproduce your problem using the code above.

 

[vbtest5]

Hi there,

Your solution worked.... Thanks a lot! It helped a lot since my project was under implementation phase.

Regards,
Varsha