appsetting in class doesn't work

Here's the class code snippet
Imports System.Configuration.ConfigurationManager

Public Class Class1

Public _strTestSetting As String



Public Sub SetTestsetting()

_strTestSetting = AppSettings.Get("TestSetting") -should get the value of
TestSetting in app config file

End Sub


End Class

This is the snippet in the project calling the class -Project TestIt - To
test you should have a setting named TestSetting application scope, value
Testvalue

Imports System.Configuration

Public Class Form1

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles Button1.Click

Dim mycls As New clsTestconfig.Class1

mycls.SetTestsetting()

Label1.Text = mycls._strTestSetting

End Sub

End Class

There's a setting TestSetting in the settings file of the project Testit

Put a breakpoint on line

_strTestSetting = AppSettings.Get("TestSetting")

Click the button, you will see as you step over the breakpoint that the
value of _strTestSetting stays at nothing. ie, its not picking up the value
of TestSetting in app.config.

How can I get this pickup of the value to work?

Thanks for any help

Bob


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