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php 字符串有长度,但内容为空?

PHP,看图,string 长度是 413,但内容为空`?这是啥原因?

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php 字符串有长度,但内容为空?

PHP,看图,string 长度是 413,但内容为空`?这是啥原因?

<?php $str = '';//your str value
for($i = 0; $i < strlen($str); $i++){
echo 'This ascii is ' . ord($str{$i}) . '<br/>';
}
?>

自己看看asc码对应的是什么就知道里面是什么东西了

和\0真没有什么关系。还是那些不可见字符。只在显示的时候空上一格
\t\n\r都会有这种效果,不过这种效果是会显示双引号中有一个空格" "
而\f\1\2\3\4\5\6\7\0,都是连空格 都没有的,即""
双引号害人啊

这个string是什么,如果贴不出来,要么就是空字符串,\r \n \t都有可能

<?php $a = "\t\t\t\t\t\t";

var_dump($a);
strint(6) "      "

多半里面有"\0"

$s="\0aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa";
var_dump($s);

HTML显示时会合并连续的空格为1个

你可以用浏览器看源码模式,

Chrome浏览器就是在地址栏前面加上view-source就行了啊

view-source:http://......
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