Summary of methods for inserting substrings into PHP strings Original, fontcolor_PHP tutorial

Summary of the method of inserting substrings into PHP strings Original, fontcolor

The example in this article describes the method of inserting substrings into PHP strings. Share it with everyone for your reference, the details are as follows:

First, let’s take a look at a common method online:

Method 1: 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);//输出：12345new_word67890

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

Let’s take a look at an improvement method given by Bangkejia:

Method 2: Use the substr function to intercept and combine

function str_insert2($str,$i,$substr){//方法二：substr函数进行截取
  $start=substr($str,0,$i);
  $end=substr($str,$i);
  $str = ($start . $substr . $end);
  return $str;
  //return substr($str,0,$i).$substr.substr($str,$i);//上述代码可综合成这一句
}
$str="1234567890";
$sstr="new_word";
echo str_insert2($str,5,$sstr);//输出：12345new_word67890

This method directly uses the substr function to intercept the string, and then assemble the string to achieve the insertion effect of the substring.

Finally, Bangkejia provides you with the most direct method:

Method 3: Directly use the substr_replace function to insert substrings

echo substr_replace($str,$sstr,5,0);
//此处直接输出：12345new_word67890

Readers who are interested in more PHP-related content can check out the special topics of this site: "Complete PHP Array Operation Skills", "PHP Data Structure and Algorithm Tutorial", "Summary of PHP Mathematical Operation Skills", "php Date and time usage summary", "php object-oriented programming introductory tutorial", "php string (string) usage summary", "php mysql database operation introductory tutorial" and "php common database operation skills summary"

I hope this article will be helpful to everyone in PHP programming.