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Valfunction
Converts a string to a floating point number
Syntax
Declare Function Val ( ByRef str As Const String ) As Double
Declare Function Val ( ByRef str As Const WString ) As Double
Parameters
| Name | Description | |
|---|---|---|
strnum | the string containing a number to convert |
Return value
Returns a converted
Double precision numberIf the first character of the string is invalid,
Val will return 0.Description
Val("10") will return 10.0, and Val("10.10") will return 10.1. The function parses the string from the left, skipping any white space, and returns the longest number it can read, stopping at the first non-suitable character it finds. Scientific notation is recognized, with "D" or "E" used to specify the exponent.Val can be used to convert integer numbers in binary / octal / hexadecimal format, if they have the relevant identifier ("&B" / "&O" / "&H") prefixed, for example: Val("&HFF") returns 255.Note:
If you want to get an integer value from a string, consider using
ValInt or ValLng instead. They are faster, since they don't use floating-point numbers, and only ValLng provides full 64-bit precision for LongInt types.If you want to convert a number into string format, use the
Str function.Remarks
Usage
result = Val( strnum )
Differences from QB
- None
See also
Example
Dim a As String, b As Double
a = "2.1E+30xa211"
b = Val(a)
Print a, b
2.1E+30xa211 2.1e+030
Reference
- Documented in KeyPgVal.html