Char.GetNumericValue Method (Char)
Converts the specified numeric Unicode character to a double-precision floating point number.
Assembly: mscorlib (in mscorlib.dll)
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 uses the ConvertFromUtf32 method to instantiate a string that represents AEGEAN NUMBER ONE. As the output from the example shows, the method returns -1 if it is passed either a high surrogate or a low surrogate of this character.
.NET FrameworkSupported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0, 1.1
.NET Framework Client ProfileSupported in: 4, 3.5 SP1
XNA FrameworkSupported in: 3.0, 2.0, 1.0
Portable Class LibrarySupported in: Portable Class Library
Supported in: Windows Phone 8.1
Supported in: Windows Phone Silverlight 8.1
Supported in: Windows Phone Silverlight 8