Question

What is the most efficient way in C# 2.0 to check each character in a string and return true if they are all valid hexadecimal characters and false otherwise?

Example

void Test() {     OnlyHexInString("123ABC"); // Returns true     OnlyHexInString("123def"); // Returns true     OnlyHexInString("123g"); // Returns false }  bool OnlyHexInString(string text) {     // Most efficient algorithm to check each digit in C# 2.0 goes here } 

Answer 1

public bool OnlyHexInString(string test) {     // For C-style hex notation (0xFF) you can use @'\A\b(0[xX])?[0-9a-fA-F]+\b\Z'     return System.Text.RegularExpressions.Regex.IsMatch(test, @'\A\b[0-9a-fA-F]+\b\Z'); }