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IsNumeric Function (Visual Basic)

Returns a Boolean value indicating whether an expression can be evaluated as a number.

Public Function IsNumeric(ByVal Expression As Object) As Boolean

Parameters

  • Expression
    Required. Object expression.

Remarks

IsNumeric returns True if the data type of Expression is Boolean, Byte, Decimal, Double, Integer, Long, SByte, Short, Single, UInteger, ULong, or UShort, or an Object that contains one of those numeric types. It also returns True if Expression is a Char or String that can be successfully converted to a number.

IsNumeric returns False if Expression is of data type Date or of data type Object and it does not contain a numeric type. IsNumeric returns False if Expression is a Char or String that cannot be converted to a number.

Example

The following example uses the IsNumeric function to determine if the contents of a variable can be evaluated as a number.

Dim testVar As Object 
Dim numericCheck As Boolean
testVar = "53" 
' The following call to IsNumeric returns True.
numericCheck = IsNumeric(testVar)
testVar = "459.95" 
' The following call to IsNumeric returns True.
numericCheck = IsNumeric(testVar)
testVar = "45 Help" 
' The following call to IsNumeric returns False.
numericCheck = IsNumeric(testVar)

Requirements

Namespace: Microsoft.VisualBasic

Module: Information

Assembly: Visual Basic Runtime Library (in Microsoft.VisualBasic.dll)

See Also

Reference

IsArray Function (Visual Basic)

IsDate Function (Visual Basic)

IsDBNull Function

IsError Function

IsNothing Function

IsReference Function

Object Data Type

TypeName Function (Visual Basic)