Visual Basic Language Reference  

Val Function

Returns the numbers contained in a string as a numeric value of appropriate type.

Public Overloads Function Val(ByVal Expression As String) As Double

-or-

Public Overloads Function Val(ByVal Expression As Object) As Double

-or-

Public Overloads Function Val(ByVal Expression As Char) As Integer

Parameter

Expression
Required. Any valid String expression, Object variable, or Char value. If Expression is of type Object, its value must be convertible to String or an ArgumentException error occurs.

Exceptions/Errors

Exception type Error number Condition
OverflowException 6 InputStr is too large.
InvalidCastException 13 Number is badly formed.
ArgumentException 438 Object type expression not convertible to String.

Remarks

The Val function stops reading the string at the first character it cannot recognize as part of a number. Symbols and characters that are often considered parts of numeric values, such as dollar signs and commas, are not recognized. However, the function recognizes the radix prefixes &O (for octal) and &H (for hexadecimal). Blanks, tabs, and linefeed characters are stripped from the argument.

The following returns the value 1615198:

Val(" 1615 198th Street N.E.")

In the code below, Val returns the decimal value -1 for the hexadecimal value shown:

Val("&HFFFF")
Note   The Val function recognizes only the period (.) as a valid decimal separator. When different decimal separators are used, as in international applications, use CDbl or CInt instead to convert a string to a number.

Example

This example uses the Val function to return the numbers contained in each string. Val stops converting at the first character that cannot be interpreted as a numeric digit, numeric modifier, numeric punctuation, or white space.

Dim ValResult As Double
ValResult = Val("2457")    ' ValResult is set to 2457.
ValResult = Val(" 2 45 7")    ' ValResult is set to 2457.
ValResult = Val("24 and 57")    ' ValResult is set to 24.

See Also

Str Function | Type Conversion Functions | OverflowException | InvalidCastException | ArgumentException