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Information.IsNumeric(Object) Method

  • Reference

Definition

Namespace:
Microsoft.VisualBasic
Assembly:
Microsoft.VisualBasic.Core.dll
Assembly:
Microsoft.VisualBasic.dll
Source:
Information.vb
Source:
Information.vb
Source:
Information.vb

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

public:
 static bool IsNumeric(System::Object ^ Expression);
public static bool IsNumeric (object? Expression);
public static bool IsNumeric (object Expression);
static member IsNumeric : obj -> bool
Public Function IsNumeric (Expression As Object) As Boolean

Parameters

Expression
Object

Required. Object expression.

Returns

Boolean

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

Examples

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)

Remarks

IsNumeric returns True if the data type of Expression is Boolean, Byte, Decimal, Double, Integer, Long, SByte, Short, Single, UInteger, ULong, or UShort. It also returns True if Expression is a Char, String, or Object that can be successfully converted to a number. Expression can contain non-numeric characters. IsNumeric returns True if Expression is a string that contains a valid hexadecimal or octal number. IsNumeric also returns True if Expression contains a valid numeric expression that begins with a + or - character or contains commas.

IsNumeric returns False if Expression is of data type Date. It returns False if Expression is a Char, String, or Object that cannot be successfully converted to a number.

Applies to

See also