Textbox Value Restriction using VB.Net

Textbox Value Restriction using VB.Net

In this tutorial, you will learn how to do textbox value restriction in allowing only specified characters or numbers based on your declared string. Also, we are using Microsoft Visual Studio 2013 as our IDE for this project. Here are the steps:

1. Open your Microsoft Visual Studio 2013 and create new project.

2. In your Form1, drag the textbox object from your Toolbox to your Form1. (see the image below).

3. Then, double click your Form1 to redirect you to its class for you to code the following:

[vbnet]

Public Class Form1

Dim valuesAllowed As String = "1234567890"
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Me.KeyPreview = True
End Sub
End Class

[/vbnet]

In this line of code, we are setting the KeyPreview property of our form to true. This will enable us to indicate whether the form will receive key events before the event is passed to the control that has focus. textbox value restriction will be able to achieve.

4. Next, click your textbox object and go to Properties > Events > and find the KeyPress event in order for the Microsoft Visual Studio to produce a line of code for that event. (refer to the highlighted event in the image below, then double click it).

5. After double clicking it, insert this line of code on your KeyPress method.

[vbnet]

Private Sub TextBox1_KeyPress(sender As Object, e As KeyPressEventArgs) Handles TextBox1.KeyPress
If Not valuesAllowed.Contains(e.KeyChar) AndAlso e.KeyChar <> ChrW(Keys.Back) Then
e.Handled = True
End If
End Sub

[/vbnet]

6. After inserting this line of code to your KeyPress method, you can now test it for yourself and see that the textbox object allows only to cater values based on your declared valuesAllowed string.(Textbox Value Restriction using VB.Net)

Here’s the full line of code in this tutorial:

[vbnet]

Public Class Form1

Dim valuesAllowed As String = "1234567890"

Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Me.KeyPreview = True
End Sub

Private Sub TextBox1_KeyPress(sender As Object, e As KeyPressEventArgs) Handles TextBox1.KeyPress
If Not valuesAllowed.Contains(e.KeyChar) AndAlso e.KeyChar <> ChrW(Keys.Back) Then
e.Handled = True
End If
End Sub

End Class

[/vbnet]

RAR Extraction Password:

Password: luffypirates

For questions or any other concerns, you can contact me through the following:

E-Mail: [email protected]

Facebook: facebook.com/kirk.lavapiez

Contact No.: +639771069640

To download the sample project with the line of codes, click here.

Ian Hero L. Lavapiez

BSIT Graduate

System Analyst and Developer

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