Case insensitive comparison of two strings using strcasecmp function

Compare strings without case sensitivity

strcasecmp() returns 0 when two strings are equal ignoring ASCII case, a negative value when the first sorts before the second, and a positive value when it sorts after.

if (strcasecmp('PHP', 'php') === 0) {
    echo 'Same text ignoring case';
}

Start with this current pattern. The examples below are retained, corrected where necessary, and expanded for additional variations and output.

echo strcasecmp("Hello world","HELLO WORLD"); // Output is 0

This is Binary safe case-insensitive compare two strings by using strcasecmp function.

Output is equal to

0 : if both strings are equal or matching
< 0 : if string 1 is less than string 2
> 0 : if string 1 is greater than string 1

Case sensitive string comparison use strcmp() function

Sample code using strcasecmp function to check two strings.
Example 1


$str1="Hello World";
$str2="hello world";
echo strcasecmp($str1,$str2); // Output is 0 
if(strcasecmp($str1,$str2)==0){
echo "Both strings are matching";
}else{
echo "Both strings are different ";
}

Output is

Both strings are matching

Example 2

$str1="Hello";
$str2="hello world";
echo strcasecmp($str1,$str2);  // Output is -6
if(strcasecmp($str1,$str2)==0){
echo "Both strings are matching";
}else{
echo "Both strings are different ";
}

Output is

Both strings are different

Example 3

$str1="Hello World";
$str2="hello";
echo strcasecmp($str1,$str2);  // Output is 6
if(strcasecmp($str1,$str2)==0){
echo "Both strings are matching";
}else{
echo "Both strings are different ";
}

Both strings are different

Example: Case-Sensitive vs Case-Insensitive Comparison

$str1 = 'Apple';
$str2 = 'apple';
echo strcmp($str1, $str2);  // Output: -1  Non-zero (case-sensitive)
echo strcasecmp($str1, $str2);  // Output: 0 (case-insensitive)

Example: Handling Empty Strings

$str1 = '';
$str2 = 'test';
echo strcmp($str1, $str2);  // Output: -1

String Functions strcmp(): Case sensitive string comparison str_replace(): String replace

Subhendu Mohapatra

Author & Instructor at plus2net

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strcasecmp(): Case insensitive string comparison

Compare strings without case sensitivity

Example: Case-Sensitive vs Case-Insensitive Comparison

Example: Handling Empty Strings

Subhendu Mohapatra