Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Me.MaskedTextBox1.Mask = "00/00/0000"
        Me.MaskedTextBox1.ValidatingType = GetType(System.DateTime)
    End Sub


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

        Dim ddd, mmm, yyy As String
        
        ddd = Mid(MaskedTextBox1.Text, 1, 2)


        If Len(Trim(ddd)) < 2 Then
            ddd = "0" & Trim(ddd)
        End If


        mmm = Mid(MaskedTextBox1.Text, 4, 2)

        If Len(Trim(mmm)) < 2 Then
            mmm = "0" & Trim(mmm)
        End If


        yyy = Mid(MaskedTextBox1.Text, 7, 4)

        If Len(Trim(yyy)) < 4 Then
            MsgBox("الرجاء ادخال السنة بالتاريخ الصحيح")
        Else
            Dim rr As Date
            rr = CDate(ddd & "/" & mmm & "/" & yyy)
            MaskedTextBox1.Text = Format(rr, "dd/MM/yyyy")
        End If

    End Sub