stripos() Position of first occurence of a case-insensitive search substring with offset

$position=stripos("Welcome to plus2et.com",'CO');
echo $position; // Output is 3

Syntax

$int_position=stripos(Main_string, Search_string,[optional: offset =0 ]);

Main_string : The string inside of which the search_string will be searched.
search_strig : This is searched within the Main_string.
offset : (optional, integer ) Starting point of search but position count is returned from beginning or ending of the string. Negative integer is allowed to search from end of the string in PHP version 7.0.1

Using Offset

Note that first position is 0 ( zero ) .
Position is returned starting from beginning of the string or from ending of the string (negative offset is added in PHP version 7.0.1). This counting of position is irrespective of given offset.

$position=stripos("Welcome to plus2et.com",'CO',4);
echo $position; // Output is 19, not 3

strpos() Position of search string with offset

Checking return value

We may get Boolean value as false and it may also return non-Boolean value. We need to evaluate the return value using === operator or !== to get the correct output. Check this code below and the outputs

$position=stripos("Welcome to plus2et.com",'y'); 
if($position==false){
echo " Not found ";	
}else{
echo " Found and position = ".$position;	
}
// Output is Not found

Using the same code we will search for sub-string W

$position=stripos("Welcome to plus2et.com",'W'); 
if($position==false){
echo " Not found ";	
}else{
echo " Found and position = ".$position;	
}
// Output is Not found

The search string ( W ) is already present at position 0 . Above code need to change like this to get correct output.

$position=stripos("Welcome to plus2et.com",'w'); 
if($position===false){
echo " Not found ";	
}else{
echo " Found and position = ".$position;	
} // Output is Found and position = 0

Use === or !== to test the return value

case-insensitive

stripos() is case insensitive

$position=stripos("Welcome to plus2et.com",'M'); 
if($position===false){
echo " Not found ";	
}else{
echo " Found and position = ".$position;	
} // Output is Found and position = 5

strpos() case-sensitive search returns position of first occurrence
strrpos() case-sensitive search returns position of last occurrence
strripos() case-insensitive search returns position of last occurrence

String Functions stristr(): String search str_replace(): String replace

Subhendu Mohapatra

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stripos() : Position of first occurence of the search ( case-insensitive )string

Using Offset

Checking return value

case-insensitive

Subhendu Mohapatra