PHP Tutorial - PHP strncmp() Function


The strncmp() function compares two strings case-sensitive for specified length.


PHP strncmp() Function has the following syntax.



ParameterIs Required Description
string1Required.First string to compare
string2Required. Second string to compare
lengthRequired. Number of characters from each string to be used in the comparison


This function returns:

  • 0 - if the two strings are equal
  • <0 - if string1 is less than string2
  • >0 - if string1 is greater than string2

Example 1

Compare two strings (case-sensitive):

echo strncmp("Hello world!","Hello earth!",6);

The code above generates the following result.

Example 2

Compare two strings (case-sensitive = Hello and hELLo will not output the same):

echo strncmp("Hello","Hello",6);
echo "<br>";
echo strncmp("Hello","hELLo",6);

The code above generates the following result.