Today I have brought you something delicious :) so you guys wonder how it works , first we have to create a module and we just have to assign the textbox for a validation (Only Number,Only Characters,Not Null,Only Email) so first of all lets create a new module and add this codes
Imports System.Text.RegularExpressions
Module Module1
Public Enum ValidationType
Only_Numbers = 1
Only_Characters = 2
Not_Null = 3
Only_Email = 4
End Enum
Public Sub AssignValidation(ByRef CTRL As Windows.Forms.TextBox, ByVal Validation_Type As ValidationType)
Dim txt As Windows.Forms.TextBox = CTRL
Select Case Validation_Type
Case ValidationType.Only_Numbers
AddHandler txt.KeyPress, AddressOf number_Leave
Case ValidationType.Only_Characters
AddHandler txt.KeyPress, AddressOf OCHAR_Leave
Case ValidationType.Not_Null
AddHandler txt.Leave, AddressOf NotNull_Leave
Case ValidationType.Only_Email
AddHandler txt.Leave, AddressOf Email_Leave
End Select
End Sub
Public Sub number_Leave(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs)
Dim numbers As Windows.Forms.TextBox = sender
If InStr("1234567890.", e.KeyChar) = 0 And Asc(e.KeyChar) <> 8 Or (e.KeyChar = "." And InStr(numbers.Text, ".") > 0) Then
e.KeyChar = Chr(0)
e.Handled = True
End If
End Sub
Public Sub OCHAR_Leave(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs)
If InStr("1234567890!@#$%^&*()_+=-", e.KeyChar) > 0 Then
e.KeyChar = Chr(0)
e.Handled = True
End If
End Sub
Public Sub NotNull_Leave(ByVal sender As Object, ByVal e As System.EventArgs)
Dim No As Windows.Forms.TextBox = sender
If No.Text.Trim = "" Then
MsgBox("This field Must be filled!")
No.Focus()
End If
End Sub
Public Sub Email_Leave(ByVal sender As Object, ByVal e As System.EventArgs)
Dim Email As Windows.Forms.TextBox = sender
If Email.Text <> "" Then
Dim rex As Match = Regex.Match(Trim(Email.Text), "^([0-9a-zA-Z]([-.\w]*[0-9a-zA-Z])*@([0-9a-zA-Z][-\w]*[0-9a-zA-Z]\.)+[a-zA-Z]{2,3})$", RegexOptions.IgnoreCase)
If rex.Success = False Then
MessageBox.Show("Please Enter a valid Email Address", "Information", MessageBoxButtons.OK, MessageBoxIcon.Information)
Email.BackColor = Color.Red
Email.Focus()
Exit Sub
Else
Email.BackColor = Color.White
End If
End If
End Sub
End Module
now lets test the module i mean lets add 4 textboxes and assign each for a validation and see whether it works !
add 4 textboxes now add labels for each like this
you can only enter numbers in textbox1
you can only enter characters in textbox2
you cannot leave textbox3 blank
you can only enter email in textbox4
now go to form_load event and add these codes
AssignValidation(Me.TextBox1, ValidationType.Only_Numbers)
AssignValidation(Me.TextBox2, ValidationType.Only_Characters)
AssignValidation(Me.TextBox3, ValidationType.Not_Null)
AssignValidation(Me.TextBox4, ValidationType.Only_Email)
thats where we assign the textbox for a validation !!
now lets test it just debug and try entering characters in textbox1 you cannot enter , go to textbox2 try entering characters you cannot enter , go to textbox3 and without entering anything go to textbox4 a message box will popup now go to textbox4 and enter something and click into another textbox and he textbox4 will be red in color and you will get a message
thanks for reading hope this is useful ! share ! comment !
