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4 methods: 1. Use the "$string variable name[0]" statement; 2. Use substr() to intercept the first character, the syntax is "substr(English string,0,1)" ; 3. Use mb_substr() to intercept the first character, the syntax is "mb_substr(Chinese string, 0,1, encoding)"; 4. Use mb_strcut() to intercept the first character, the syntax is "mb_strcut(Chinese string, 0 ,3,encoding)" or "mb_strcut(English string,0,1,encoding)".
The operating environment of this tutorial: windows7 system, PHP version 8.1, DELL G3 computer
php gets the string Several methods for the first character in
Method 1: Use the $string variable name[0] statement to obtain the
Seen as a character collection (array), the first value of the array is the value of the element with index 0.
Note: Chinese strings are not applicable!
<?php header('content-type:text/html;charset=utf-8'); $str = 'hello'; echo "原字符串为："; var_dump($str); echo "字符串的第一个字符为：".$str[0]; ?>
Method 2: Use the substr() function to intercept the first character
The substr() function can extract the first character from the string Intercept characters of a certain length at the specified position.
substr(string,start,length)
| Parameters | Description |
|---|---|
| string | Required . Specifies a part of the string to be returned. |
| start | Required. Specifies where in the string to begin.
|
| length | Optional. Specifies the length of the string to be returned. The default is until the end of the string.
|
Just set the second parameter of the function to 0 and the third parameter to 1
<?php header('content-type:text/html;charset=utf-8'); $str = 'Ahello'; echo "原字符串为："; var_dump($str); echo "字符串的第一个字符为：".substr($str,0,1)."<br>"; ?>
Note: Chinese strings are not applicable!
Method 3: Use the mb_substr() function to intercept the first character
The mb_substr() function can intercept a specified part of a string, similar to substr() The difference between the functions is that the mb_substr() function is not only valid for English characters, but also for Chinese characters.
mb_substr(string,start,length,encoding)
| Parameters | Description |
|---|---|
| str | Required . Extracts a substring from this string. |
| start | Required. Specifies where in the string to begin.
|
| length | Optional. Specifies the length of the string to be returned. The default is until the end of the string.
|
| encoding | Optional. Character Encoding. If omitted, the internal character encoding is used. |
You only need to set the second parameter of the function to 0 and the third parameter to 1
<?php header('content-type:text/html;charset=utf-8'); $str = 'Mhello'; echo "原字符串为："; var_dump($str); echo "字符串的第一个字符为：".mb_substr($str,0,1,"utf-8")."<br><br><br>"; $str = '欢迎来到PHP中文网'; echo "原字符串为："; var_dump($str); echo "字符串的第一个字符为：".mb_substr($str,0,1,"utf-8")."<br>"; ?>
Method 4: Use mb_strcut() to intercept the first character
mb_strcut() and mb_substr() are somewhat similar and can be set Character encoding, but the difference is that mb_substr splits characters by words, while mb_strcut splits characters by bytes but does not produce half a character. That is:
mb_substr() function represents a unit for either English or Chinese characters.
mb_strcut() function has 3 units for Chinese characters and 1 unit for English characters.
<?php header('content-type:text/html;charset=utf-8'); $str = 'Bhello'; echo "原字符串为："; var_dump($str); echo "字符串的第一个字符为：".mb_strcut($str,0,1,"utf-8")."<br><br><br>"; $str = '欢迎来到这里'; echo "原字符串为："; var_dump($str); echo "字符串的第一个字符为：".mb_strcut($str,0,3,"utf-8")."<br>"; ?>
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