计算字符串中前导零的数量

Question

i need to count leading zeros in string.

this is what i found count leading zeros in integer

    static int LeadingZeros(int value)
{
   // Shift right unsigned to work with both positive and negative values
   var uValue = (uint) value;
   int leadingZeros = 0;
   while(uValue != 0)
   {
      uValue = uValue >> 1;
      leadingZeros++;
   }

   return (32 - leadingZeros);
}

but couldn't found counting leading zeros in string.

string xx = "000123";

above example have 000 so i want to get result count number as 3

how i can count zeros in string?

if anyone tip for me much appreciate

Answer 1

The Simplest approach is using LINQ :

var text = "000123";
var count = text.TakeWhile(c => c == '0').Count();

Answer 2

int can't have leading 0 's, however I assume you just want to count leading zeros in a string.

Without getting fancy, just use a vanilla for loop:

var input = "0000234";
var count = 0;

for(var i = 0; i < input.Length && input[i] == '0'; i++)
   count++;

Full Demo Here