


Solution to the problem of intercepting Chinese garbled characters with PHP substr_PHP tutorial
PHP provides us with several character interception functions, including substr, mb_substr, and mb_strcut functions. Some of our PHP beginners will use substr to intercept Chinese characters. It turns out that the Chinese characters will be garbled. If garbled characters appear, we can use mb_substr to solve.
The description of the article page uses the substr function to intercept 220 characters, but the last Chinese character is always garbled, and the intercepted length is incorrect.
Find the method through the magic of Google. It may be because substr(string,start,length) will truncate Chinese characters into characters, resulting in garbled characters
Solution:
Use the mb_substr method in the PHP extension library.
Attention
1. Make sure you have the php_mbstring.dll file in Windows/system32. If not, copy it from your Php installation directory extensions into Windows/system32.
2. Find php.ini in the windows directory, open it for editing, search for mbstring.dll, and find
;extension=php_mbstring.dll remove the previous; sign so that the mb_substr function can take effect
Method definition:
string mb_substr ( string str, int start [, int length [, string encoding]] )
Note: When using mb_substr()/mb_strcut, you need to add one more parameter at the end to set the encoding of the string,
For example:
The code is as follows | Copy code | ||||
|
代码如下 | 复制代码 |
$description = mb_substr(strip_tags($post->post_content),0,220,’utf-8′); |
The code is as follows | Copy code |
$description = mb_substr(strip_tags($post->post_content),0,220,’utf-8′); |
The mb_strcut function can also intercept the length of a string. The following example shows the difference:
代码如下 | 复制代码 |
$str = '这样一来我的字符串就不会有乱码^_^'; echo "mb_substr:" . mb_substr($str, 0, 7, 'utf-8'); echo "mb_strcut:" . mb_strcut($str, 0, 6, 'utf-8'); |
The code is as follows | Copy code |
$str = 'This way my string will not be garbled^_^';
echo "mb_substr:" . mb_substr($str, 0, 7, 'utf-8');
//Result: This way my words
echo " "; echo "mb_strcut:" . mb_strcut($str, 0, 6, 'utf-8'); //Result: like this ?> |
As can be seen from the above example, mb_substr splits characters by words, while mb_strcut splits characters by bytes, but neither will produce half a character.
Chinese version of substr() function The ordinary substr() function can obtain the substring of the specified length of the string, but when encountering Chinese, garbled characters may be generated at the end of the new string. The following function will exceed the length of $len. The string is converted to end with "..." and garbled characters are removed.
Usage: $new = getsubstring($old,20);
The code is as follows
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function getsubstring($str,$len) |

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