Error while inheriting textbox in vb.net

Question

I am working on one assignment to Create a user control inheriting a text box which would allow only capital alphabets. i am still working with it. below is the code which i have worked till now.

Imports System.ComponentModel
Imports System.Windows.Controls

Partial Public Class textboxupper_uc

 Inherits TextBox

    Dim strUpperText As String

    Sub New()
        InitializeComponent()
    End Sub

    Public Property uppText As String
        Get
            Return strUpperText
        End Get
        Set(value As String)
            strUpperText = value.ToUpper
        End Set
    End Property
End Class

the line Inherits TextBox giving error as "Base class "TextBox" specified for class 'textboxupper_uc' can not be different from the base class 'user control' of one of its other partial types."

Given that this is an assignment, I guess you have to do what it says. The things is though, you can simply set the CharacterCasing property of a standard TextBox to Upper and then anything typed in will be displayed in upper-case. — jmcilhinney
– jmcilhinney, Commented Apr 23, 2018 at 7:14

jmcilhinney · Accepted Answer · 2018-04-23 07:12:25Z

1

You need to understand the difference between a user control and a custom control. If you want to inherit the TextBox class then that is a custom control. A user control is literally a class that inherits UserControl.

If you added a user control to your project then you have two code files containing partial classes. The designer code file contains Inherits UserControl and that's why you get that error message. Your class cannot inherit both UserControl and TextBox.

You don't actually want a user control so delete that item from the Solution Explorer. You want a custom control, you should add a class item to your project rather than a user control. In the class definition in the single code file, you can then add Inherits TextBox and you're good to go.

answered Apr 23, 2018 at 7:12

jmcilhinney

54.9k5 gold badges30 silver badges52 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Error while inheriting textbox in vb.net

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related