PHP - 检查字符串是否只有少于4个字符的单词

Question

I need to check if a query string is made up solely with words of less than 4 characters, then remove all white spaces if it is true.

So something like: this has four character words or higher ... would return FALSE

Something like: hd 1 kit ... would return TRUE as no word in the string is greater than 3 characters.

I'd try coding it but haven't the slightest clue on how to write a regex for something like this.

Answer 1

Hope this simple solution will help you out.

Regex: /\b[a-zA-Z0-9]{4,}\b/

1. \b[a-zA-Z0-9]{4,}\b will match will four characters and \b is for boundry condition.

<?php

$string1="this has four character words or higher";
$string2="hd 1 kit";

if(!preg_match_all("/\b[a-zA-Z0-9]{4,}\b/", $string1))
{
    echo "Should be allowed";
}