C # leading zeros for a negative number

Question

How to remove trailing zeros on negative numbers in C #?

For example, I want to convert '-01' to '-1'.

Answer 1

Assuming your input will be an actual string, you can use any of the common parsing methods, for example Int32.Parse() or Convert.ToInt32() should handle leading zeros:

 Convert.ToInt32("-01"); // yields -1 

Behind the scenes

If you dig into the implementation of these methods , you will see that it calls the base method StringToNumber() and the subsequent ParseNumber() , which should take care of handling the leading and trailing zeros:

 // This is called via the following methods // 1.) Convert.ToInt32() // 2.) Int32.Parse() // 3.) Number.ParseInt32() // 4.) StringToNumber() (this method) // 5.) ParseNumber() (called by this method) [System.Security.SecuritySafeCritical] // auto-generated private unsafe static void StringToNumber(String str, NumberStyles options, ref NumberBuffer number, NumberFormatInfo info, Boolean parseDecimal) { if (str == null) { throw new ArgumentNullException("String"); } Contract.EndContractBlock(); Contract.Assert(info != null, ""); fixed (char* stringPointer = str) { char * p = stringPointer; if (!ParseNumber(ref p, options, ref number, null, info , parseDecimal) || (p - stringPointer < str.Length && !TrailingZeros(str, (int)(p - stringPointer)))) { throw new FormatException(Environment.GetResourceString("Format_InvalidString")); } } } private static Boolean TrailingZeros(String s, Int32 index) { // For compatability, we need to allow trailing zeros at the end of a number string for (int i = index; i < s.Length; i++) { if (s[i] != '\0') { return false; } } return true; } 

Answer 2

You can try string parsing:

 var negativeStrNum = "-000005"; Console.WriteLine(int.Parse(negativeStrNum)); 

It gives you -5

Answer 3

What about int.Parse("-01").ToString() ?

Answer 4

  string InputString = "-020.50"; for (int i = 0; i < InputString.Length; i++) { char CurrentCharacter = InputString[i]; if (Char.IsDigit(CurrentCharacter)) { if (CurrentCharacter == '0') { InputString = InputString.Remove(i, 1); i--; } else break; } } Console.WriteLine(InputString);