Char.GetNumericValue Method (Char)
[ This article is for Windows Phone 8 developers. If you’re developing for Windows 10, see the latest documentation. ]
Converts the specified numeric Unicode character to a double-precision floating point number.
Assembly: mscorlib (in mscorlib.dll)
Parameters
- c
- Type: System.Char
A Unicode character.
Return Value
Type: System.DoubleThe numeric value of c if that character represents a number; otherwise, -1.0.
The c parameter must be the Char representation of a numeric value. For example, if c is '5', the return value is 5. However, if c is 'z', the return value is -1.0.
A character has an associated numeric value if and only if it is a member of one of the following UnicodeCategory categories: DecimalDigitNumber, LetterNumber, or OtherNumber.
The GetNumericValue method assumes that c corresponds to a single linguistic character and checks whether that character can be converted to a decimal digit. However, some numbers in the Unicode standard are represented by two Char objects that form a surrogate pair. For example, the Aegean numbering system consists of code points U+10107 through U+10133. The following example instantiates a string that represents AEGEAN NUMBER ONE. As the output from the example shows, the GetNumericValue method returns false if it is passed either a high surrogate or a low surrogate of this character.
The following example demonstrates GetNumericValue.