Insert Substring Method Summary in PHP string

This article mainly introduces the Insert Substring method in PHP string, compares and analyzes the string traversal, substr method interception and combination, and directly uses the Substr_replace function to insert three different implementations of substrings, involving the common techniques of PHP string manipulation, A friend you need can refer to the following

This example describes the insertion of a substring method in a PHP string. Share to everyone for your reference, as follows:

First look at a common online approach:

Method One: String traversal

function Str_insert ($str, $i, $substr) {for  ($j =0; $j < $i; $j + +) {    $startstr. = $str [$j];  }  for ($j = $i; $j <strlen ($STR); $j + +) {    $laststr. = $str [$j];  }  $str = ($startstr. $substr. $laststr);  return $STR;} $str = "1234567890"; $sstr = "New_word"; Echo Str_insert ($str, 5, $SSTR);//output: 12345new_word67890

The above method uses the string traversal reorganization to implement the substring insertion function.

Let's look at an improved approach given by the Scripting House:

Method Two: Using SUBSTR function to intercept and combine

function Str_insert2 ($str, $i, $substr) {//Method two: substr function to intercept  $start =substr ($str, 0, $i);  $end =substr ($str, $i);  $str = ($start. $substr. $end);  return $str;  Return substr ($str, 0, $i). $substr. substr ($str, $i);//The above code can be synthesized into this sentence} $str = "1234567890"; $sstr = "New_word"; Echo str_ Insert2 ($str, 5, $SSTR);//output: 12345new_word67890

The method uses the SUBSTR function to intercept the string, and then assemble the string to achieve the insertion effect of the substring.

The final script house provides you with one of the most straightforward methods:

Method Three: Inserting substrings directly using the Substr_replace function

Echo Substr_replace ($str, $sstr, 5,0);//Direct output here: 12345new_word67890