Little But Big Code Problem

Question

User988538322 posted

hi its my Code 

 Dim a, b As String

    Public Sub TestStr(ByVal Str As String)
        Str = "abc"
    End Sub

    Public Sub TestText(ByVal Text As TextBox)
        Text.Text = "abc"
    End Sub

    Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
        TestStr(a)
        TestText(TextBox2)

        TextBox1.Text = a
        b = TextBox2.Text
    End Sub

the problem is TextBox fill Successfully but String can not be filled. it shows empty. Please Help