validation textbox

[eugz]

Hi All.
I validate TextBox for numeric and legth no more then 7 characters. I'm checking for Not IsNumber and Len. But I want to give a user to save record when TextBox is blank. If is it possible how to do it?
Thanks.

[gep13]

Hey,

I am not sure that I fully understand the question?!?

Can you provide more details, plus the code you are already using?

Gary

[JuggaloBrotha]

Dim BogusDec As Decimal
If (TextBox.Text.Trim.Length = 0I OrElse TextBox.Text.Trim.Length = 7I) AndAlso Decimal.TryParse(TextBox.Text.Trim, BogusDec) Then
  'Good to go
End If

[gep13]

Hey,

If that is what the OP is trying to do, then I would be tempted to implement this as a Regular Expression check:

http://www.java2s.com/Tutorial/CShar...oraTextBox.htm

Hope that helps!!

Gary

[Siddharth Rout]

Not Sure but do you have something like this in vb.net?

Dim BogusDec As Decimal
If TextBox.Text.Trim.Length < 8I AndAlso Decimal.TryParse(TextBox.Text.Trim, BogusDec) Then
  'Good to go
End If

[stanav]

Regex is kind of over kill for this simple validation.
Set the textbox.MaxLength = 7 and handle the textbox.validating event. In the event handler, just test if the text is not blank and do a tryparse to make sure it's a valid number.

[Pradeep1210]

Not Sure but do you have something like this in vb.net?

Dim BogusDec As Decimal
If TextBox.Text.Trim.Length < 8I AndAlso Decimal.TryParse(TextBox.Text.Trim, BogusDec) Then
  'Good to go
End If

You don't need to declare that variable if you won't be using it. You can simply pass Nothing for it.

If TextBox.Text.Trim.Length < 8 AndAlso Decimal.TryParse(TextBox.Text.Trim, Nothing) Then
  'Good to go
End If

[/QUOTE]

[JuggaloBrotha]

You don't need to declare that variable if you won't be using it. You can simply pass Nothing for it.

If TextBox.Text.Trim.Length < 8 AndAlso Decimal.TryParse(TextBox.Text.Trim, Nothing) Then
  'Good to go
End If

Didn't know that one, I thought it had to be an actual variable whether you use it or not. It would be nice if the String class had a .IsNumber function like the Char class does.

[gep13]

How about creating an Extension method?

http://dotnetbyexample.blogspot.com/...n-methods.html

Gary

[Pradeep1210]

Its easy to create extension methods.

e.g.

Public Module MyExtensionMethods
    <Extension()> _
    Public Function IsNumber(ByVal input As String) As Boolean
        Return Decimal.TryParse(input, Nothing)
    End Function
End Module

So now you use it just like any other method of the String class:
e.g.

Dim myString as String = "12345"
MessageBox.Show(myString.IsNumber)

[chris128]

Didn't know that one, I thought it had to be an actual variable whether you use it or not. It would be nice if the String class had a .IsNumber function like the Char class does.

I guess it would be nice, but you can just use the IsNumeric function instead

[Pradeep1210]

I guess it would be nice, but you can just use the IsNumeric function instead

The IsNumeric function is good for ordinary use. But it usually won't give the results you would expect. It actually tries anything that can be possible as a number. e.g. hex numbers, commas etc. which you might not expect in normal ways.

e.g.

Decimal.TryParse("&H10A", Nothing)          '<-- Returns False
IsNumeric("&H10A")                          '<-- Returns True

[chris128]

Oh right, I never knew that, thanks