PHP substring function


Answers ( 1 )


    It is about how to extract a part of a string in PHP.

    In PHP, you can use several functions to extract a substring. The most commonly used ones are substr() and mb_substr(). The choice between these functions usually depends on whether you are dealing with multibyte character encodings like UTF-8.

    1. Using substr():

      • This function is used for single-byte character encodings. It takes three parameters: the string, the start position, and the length of the substring.
      • If the start position is positive, the substring starts from that position counting from the beginning. If it's negative, it starts that far from the end of the string.
      • The length parameter is optional. If it's provided, it represents the length of the substring. If it's omitted, the substring extends from the start position to the end of the string.


      $string = "Hello World";
      $substring = substr($string, 6, 5); // Outputs "World"
    2. Using mb_substr():

      • This function is similar to substr() but is used for multibyte character encodings like UTF-8.
      • It's part of the Multibyte String extension in PHP, which provides functions to deal with multibyte encodings. It's especially important when dealing with languages that have characters outside the ASCII range.


      $string = "こんにちは世界"; // "Hello World" in Japanese
      $substring = mb_substr($string, 0, 5); // Outputs "こんにちは" (Hello)

    Remember to enable the Multibyte String extension if you are using mb_substr() and dealing with multibyte characters. This can usually be done by uncommenting the line extension=mbstring in your php.ini file or installing the extension if it's not already installed.

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