PHP substr_compare() Function

PHP substr_compare() Function

The substr_compare() function in PHP compares two strings from a specified start position. It is a binary-safe and optionally case-sensitive function.

Syntax

substr_compare ( string $main_str , string $str , int $offset [, int $length [, bool$case_insensitivity]] ) 

Parameter

main_str(required)- This parameter specifies the first string to compare.

str(required)- This parameter specifies the second string to compare 

offset(required)- This parameter represents the start position for the comparison. If this parameter is negative, it starts counting from the end of the string.

length(optional)- It signifies the length of the comparison.

case_insensitivity(optional)- This parameter signifies the boolean value that specifies whether to perform a case-sensitive comparison or not. If it set to true, the comparison is case insensitive else for False(default) the comparison is case-sensitive.

Return

This function returns the following values:

• 0 – if both the strings are equal
• <0 - if main_str (from offset) is less than str
• >0 - if main_str (from offset) is greater than str

If length is equal or greater than the length of main_str, this function returns FALSE.

Example 1

Output

String 1: Hello World
String 2: Hello PHP
The substr_compare() will return 1 

Example 2

Output

717041
0
0 

Example 3

str2
 echo("\n"); 
 echo substr_compare("abcdefg", "cd", 1, 2); // return -65793
 ?> 

Output

0
1
-65793 

Example 4

Output

PHP Warning:  substr_compare(): The length must be greater than or equal to zero in /workspace/Main.php on line 7