Testing for a number?

[Rob Meade]

Hi all,

Ok, I'm used to VBScript with stuff like IsNumeric and the like...

How can I test a value is a numeric value in .net / win forms?

I have multiple text boxes and the user is able to enter numbers like thus:

1.01
5.50

and so on, I have some formatting going on to always return 2 decimal places
etc, but how can I test this is a number?

Also, when I set my variables when the button is clicked, should I take all
of the values as 'strings' to start with and then convert them (or try to) ,
or should I declare them as what I want them to be and then try to trap the
errors when they fail...ie, someone enters:

adfsd

in my nice number box....

Any info appreciated

Regards

Rob

 

[Tim Wilson]

You might consider authoring, or locating on the internet, a control that
restricts the key strokes to only numeric, and other appropriate number
formatting, keys.

Here is one example, although I'm not exactly sure how good it is because I
haven't had a need to use it.
http://www.codeproject.com/cs/miscctrl/numedit.asp

I'm sure if you google for others you will find more.

 

[Herfried K. Wagner [MVP]]

Ok, I'm used to VBScript with stuff like IsNumeric and the like...

How can I test a value is a numeric value in .net / win forms?

Use 'Double.TryParse' to test/convert a string for/to a number.