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文本中的换行与缩进详解

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May 19, 2016 pm 12:16 PM

无意碰到了个sql安装程序,其中有以下代码

$sql = file_get_contents($sqlfile);//获取sql文件内容    $sql = str_replace("\r\n", "\n", $sql);//如在wiin下,把换行符换为\n
$sql = str_replace("\r", "\n", $sql);//如在mac下把换行符换为\n

因为我是在windows平台下,所以刚开始分析代码时,觉得无法理解第三行(只知道win下换行填充的是\r\n,linux下是\n,mac下不知道,后经查询后知是\r).

于是以上代码意义豁然开朗,原来是把三个平台下的换行符统一为\n罢了...没什么好奇怪的...

但此时,新的疑问又产生了,win下文本文件中缩进这些空间填充的又是什么呢?心里面认为答案是:\t..下用ue的十六进制模式下进行实测,以下是截图

由于显示的问题,再复述一下,由以下可知,win下\r\n的十六进制为0x0D0A,缩进是用空格填充而成,十六进制码为0x20

SSMS中使用自动换行功能读取T-SQL代码

http://tech.cncms.com/shujuku/mssql/67904.html

SQL中的换行符

http://tech.cncms.com/shujuku/mssql/67982.html

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