The replaceFirst helper method is used to replace the first occurrence of a given $search string with the provided $replace string in the $subject string. All three parameters are required and must be strings.

The signature for the replaceFirst helper method is:

replaceFirst($search, $replace, $subject)

The following examples highlight the basic usage of the replaceFirst method. The results of the method call will appear above the call as a comment.

 1use Illuminate\Support\Str;
 2 
 3// //maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css
 4Str::replaceFirst(
 5    'http://', '//',
 6    'http://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css'
 7);
 8 
 9// Hello, there!
10Str::replaceFirst('there', 'Hello', 'there, there!');

#str_replace_first($search, $replace, $subject)

The str_replace_first function is a shortcut to calling Str::replaceFirst. This function is declared in the global namespace.

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