How to check if string or boolean

[TonyScarpelli]

I'm looking for a function that can tell me if a string is a string or not, and a boolean is a boolean or not.

In FoxPro we have a Type() function that does that.

Is there something equivalent in VB.Net?

Thanks.


Tony Scarpelli
Clinical Engineering Dept.
Maine Medical Center
Portland, Maine 04102

 

[JohnYingling]

See TypeOf and TyprName

http://www.VBResizer.com

Forms/Controls Resizing/Tabbing

http://www.VBCompare.com

Compare Code

http://www.VBSortGen.com

Generate Sort Class in VB

http://www.Vbcompare.com/Check.Htm(1979

Check To MS)

 

[chiph]

Since .NET is strongly typed, a variable of type Boolean will always contain values that are appropriate to it's datatype. So you are guaranteed to always get either "true" or "false" out of one.

Same thing applies to a String. It will always contain a string value (or String.Empty). Note that a string value can be a string representation of other datatypes (since you can call ToString() on anything), but it's still a valid string.

Chip H.


____________________________________________________________________
If you want to get the best response to a question, please read FAQ222-2244 first

 

[JohnYingling]

Chip
A String does not always contain a value.
Dim s As String ' Is Nothing

If s.Length = 0 Then ' Throws exception
End If

BUT
If s = String.Empty Then ' is True

http://www.VBResizer.com

Forms/Controls Resizing/Tabbing

http://www.VBCompare.com

Compare Code

http://www.VBSortGen.com

Generate Sort Class in VB

http://www.Vbcompare.com/Check.Htm(1979

Check To MS)

 

[chiph]

Ahh, you're right. I had forgotten that string is a reference type, not a value type like Boolean.

So, there is a chance that it could be Nothing/null.

Chip H.


____________________________________________________________________
If you want to get the best response to a question, please read FAQ222-2244 first