How use MaskedTextBox Control

Drag and drop MaskedTextBox and Button (change its caption to Submit) control from toolbox on the window Form.

Code:

PublicClass Form10
  
    PrivateSub Form10_Load(ByVal sender As System.Object, ByVal e As System.EventArgs)  HandlesMyBase.Load
        'Here TextBox is masked as number show you can enter number only
         MaskedTextBox1.Mask = "00000000000000000"
    EndSub
  
    PrivateSub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs)  Handles Button1.Click
        'Enter number will show in Label
         Label2.Text = "Entered Number is  " + MaskedTextBox1.Text
    EndSub
EndClass

Run The Project

When you enter other than number then masketextbox will not accept.Because in code mask is specified as  MaskedTextBox1.Mask = "00000000000000000" which means it will accept only number.

When you enter number and click Submit Button then click event of submit button will fire and entered number will show in the Label.

MaskedTextBox Property

UseSystemPasswordChar: Gets or sets a value indicating as password character.

PrivateSub Form10_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) HandlesMyBase.Load
        ' entered number will show as password
         MaskedTextBox1.UseSystemPasswordChar = True
EndSub

ForeColor:

ForeColor ofMaskedTextBox can be changed through ForeColor property of MaskedTextBox.

PrivateSub Form10_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) HandlesMyBase.Load
        'change ForeColor of MaskedTextBox
         MaskedTextBox1.ForeColor = Color.Red
EndSub

ForeColor  of MaskedTextBox will bechanged.