Check if type is numeric or not?

Check if type is numeric or not?

• Lester Leonard Go

  Integers and Doubles always have a value - the default is 0.
  
  If you have a string and want to check if it represents a number, use Integer.TryParse or Double.TryParse. If the string is a number, that value will be assigned to the out parameter.
  
  

• Stephen Weatherford MS

  Well I am basically just assinging an integer to a column index in a grid, so even the default 0 is available. I was just thinking there must be a way to check if my integer got assigned yet. But knowing it should be greater than 0(Col index) then I should be able to just place a check to see if myinteger > 0 That should work I think.
  
  
  Thanks.
  
  
  

• Julie Brazier

  In .NET 2.0, you can use Nullable(Of Int). If you don't assign a value to that, if will return null (Nothing in VB).
  
  Otherwise, you could override the default value by declaring your variable as Dim x As Integer = -1
  
  

• rfolk73

  Are you asking how to check if a number has anything but zero in it
  
  As numbers (integers, doubles, floats, etc) are value types, they always have a value assigned to them.
  
  For example, the number variable below has the default value of 0 and hence the first message box will be displayed.
  
  

  Dim number as Integer; If number = 0 Then    MessageBox.Show("number is zero!.") Else         MessageBox.Show("number is not zero!.") End if

  
  
  
  
  
  
  

  
  
  

• lauch

  Vikram,
  
  Good point, just fixed it. That will teach me for typing code without testing it.
  
  

• coozdrm

  Hi,
  
  You seem to have mixed up C# and VB in the code snippet!
  It should be as follows in VB:
  
  

  Dim number As Integer If (number = 0) Then    MessageBox.Show("number is zero!.") Else    MessageBox.Show("number is not zero!.") End If

  
  
  Regards,
  Vikram

  
  
  
• Check if type is numeric or not?