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php can loop strings. In PHP, strings can be used as arrays. The characters in the string can be searched and modified by starting with 0 and containing the corresponding numbers in square brackets similar to the array structure; therefore, it can also be used like a loop Looping a string like an array), the syntax for looping a string is "for($i=0;$i
The operating environment of this tutorial: windows7 system, PHP version 8.1, DELL G3 computer
php can loop strings.
In PHP, strings can be used as arrays (so strings can also be looped like arrays).
The following are relevant instructions from the official PHP user manual:
The characters in the string can start with 0, and use square brackets similar to the array structure to contain the corresponding numbers. To search and modify, such as $str[42]
, you can think of the string as an array, so that you can take out a character at the specified position. The functions substr() and substr_replace() can be used to implement more than one character.
<?php header('content-type:text/html;charset=utf-8'); $str = "hello"; echo $str."<br>"; echo $str[0]."<br>"; echo $str[1]."<br>"; echo $str[2]."<br>"; ?>
Numbers in square brackets outside the range will produce blanks. Non-integer types are converted to integers, and non-integer types are converted to integers. Illegal types will generate an E_NOTICE level error. Negative numbers will generate an E_NOTICE when written, but an empty string will be read. Only the first character of the specified string is available, and an empty string is specified as a null byte.
php loop string example:
Because the string can be regarded as a class index array whose subscript starts with 0. So below we can use the for statement to loop the string
<?php $str = "hello"; var_dump($str); for($i=0;$i<strlen($str);$i++){ echo $str[$i]."<br>"; } ?>
Note: the foreach statement is invalid for strings and will report an error
foreach ($str as $value){ echo $valu."<br>"; }
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