PHP,看图,string 长度是 413,但内容为空`?这是啥原因?
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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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