PHP deletes whitespace characters at the end of the string function chop()-PHP Tutorial-php.cn

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PHP deletes whitespace characters at the end of the string function chop()

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Nov 01, 2017 am 10:39 AM

phpcharacterstring

定义和用法

chop() 函数移除字符串右侧的空白字符或其他预定义字符。

语法

chop(string,charlist)

chop执行去除空格处理,get_html_translation_table返回转化列表到变量,定义包括HTML编码的字符串htmlentities,htmlspecialchars_decode 定义包含HTML特殊字符的字符串,nl2br quotemeta rtrim等.

定义和用法:chop() 函数从字符串的末端开始删除空白字符或其他预定义字符,该函数的 rtrim() 函数的别名.

语法:chop(string,charlist),代码如下:

复制代码代码如下:

$str="i&#39;m a   teacher  ";          //定义字符串 
$result=chop($str);           //执行去除空格处理 
echo $result;            //输出结果

参数描述

string 必需。规定要检查的字符串。

charlist 可选。规定从字符串中删除哪些字符。
如果 charlist 参数为空，则移除下列字符：

"\0" - NULL
"\t" - 制表符
"\n" - 换行
"\x0B" - 垂直制表符
"\r" - 回车
" " - 空格

技术细节返回值：

返回已修改的字符串。

实例 1

移除字符串右侧的换行符（\n）：

<?php
$str = "Hello World!\n\n";
echo $str;
echo chop($str);
?>

上面代码的 HTML 输出如下（查看源代码）：

<!DOCTYPE html>
<html>
<body>
Hello World!
Hello World!
</body>
</html>

上面代码的浏览器输出如下：

Hello World! Hello World!

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