HI,

How can i call a method to validate atext box in windows forms?
I have currently written as
this.txtmno.LostFocus=Validate(txtmno.Text);
but its displaying error as the event "System.Windows.Form.Control.LostFocus should be on leftside of the =+-.
what may be possible solution to this.

Thanks

Prasnana

__________________
Thanks

Prasanna

Firstly you have posted it in wrong subforum.
Secondly LostFocus is an event and you have wrongly tried to set value.

Hi,

18. Validating the data entered in the Amount TextBox control.

This event occurs when the input focus leaves the control. This event procedure is to check for whether data entered in amount text box control is valid.  

Private Sub mAmount_LostFocus(ByVal sender As Object, ByVal e As System.EventArgs) Handles mAmount.LostFocus
    If Not IsNumeric(mAmount.Text) And mAmount.Text <> " " Then
        MsgBox("Not a Numeric Input! Try again.")
        mAmount.Focus()
        Exit Sub
    ElseIf (mAmount.Text < 0) Then
        MessageBox.Show("Enter positive Amount")
        mAmount.Focus()
        Exit Sub
    End If
End Sub


The TextChanged event occurs when the content in the TextBox control is changed. Select mAmount in LHS combobox and TextChanged in the RHS combobox to program this event. We use IsNumeric() function  to check the value  entered in the amount text box control is numeric data. We also check whether the value entered in this text box is empty.  If any of these conditions are true, then we will display a message box and set the focus to the Amount text box control.
 
Private Sub mAmount_TextChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles mAmount.TextChanged
    If Not IsNumeric(mAmount.Text) And mAmount.Text <> " " Then
        MsgBox("Not a Numeric Input! Try again.")
        mAmount.Focus()
        Exit Sub
    End If
End Sub