PHP implements carriage return and line feed output in html source code_PHP tutorial

PHP implements carriage return and line feed output in html source code

To enter a line feed in the source code but do not display characters like br, we need to escape characters through PHP. Let’s take a look below.

Knowledge expansion

转移序列	说明
n	换行
r	回车
t	水平制表符
[/td>	反斜线
$	美元符号
"	双引号
[0-7]{1,3}	此正则表达式序列匹配一个用八进制符号表示的字符
x[0-9A-Fa-f]{1,2}	此正则表达式序列匹配一个用十六进制符号表示的字符

Use double quotes (") to define strings. PHP understands more escape sequences of special characters:

The default page encoding of PHP is HTML. To wrap the output content, you must use the HTML line break tag "
" or "
"
, when using PHP for http api, it is a little troublesome to process the br tag. At this time, you can specify the PHP page encoding so that "＼n" can be successfully parsed into a newline.

The code is as follows

Copy code

代码如下	复制代码
header("Content-type:text/txt; charset=gb2312"); for ($i=0; $i < 100; $i++) { echo "string"; echo "＼n"; ?>

header("Content-type:text/txt; charset=gb2312");
for ($i=0; $i < 100; $i++) {

echo "string";

代码如下	复制代码
header("Content-Type: plain/text; charset=gb2312");

echo "＼n";

?>

Access with a browser, and 100 lines of "string" will be displayed directly.

You can also declare the page encoding as

The code is as follows

Copy code

header("Content-Type: plain/text; charset=gb2312");

代码如下
$filename = 'file.txt'; $word = '你好！＼r＼n欢迎来到www.111cn.net'; $fh = fopen($filename, "a"); //w从开头写入 a追加写入 echo fwrite($fh, $word); fclose($fh); ?>

At this time, if you access it with a browser, it will be automatically downloaded as a document. There is no difference when downloading with code. Newlines do not work when writing txt files using fwrite We all know the line break character of PHP: ＼n, and the carriage return character: ＼r. When a line break is needed, the combination of "＼r＼n" is usually used. But why does the \n newline character not work when we use fwrite to write a file? Let’s look at the following example first:

The code is as follows
$filename = 'file.txt';<🎜> $word = 'Hello! ＼r＼nWelcome to www.111cn.net';<🎜> $fh = fopen($filename, "a"); //w is written from the beginning and a is appended <🎜> echo fwrite($fh, $word);<🎜> fclose($fh);<🎜> ?>

The carriage return and line feed character "＼r＼n" is added to the string of $word, but the output result is not as expected. This carriage return and line feed character "＼r＼n" is not parsed as a line feed character, but It is directly output as a character.

Why does this happen? After some research, it turned out that the single and double quotation marks were to blame! We just need to replace the single quotes "'" in the $word definition string with double quotes """. The correct way to write it is as follows:

The code is as follows

代码如下
$filename = 'file.txt'; $word = "你好！＼r＼n欢迎来到www.111cn.net"; $fh = fopen($filename, "a"); //w从开头写入 a追加写入 echo fwrite($fh, $word); fclose($fh); ?>

$filename = 'file.txt';
$word = "Hello!＼r＼Welcome to www.111cn.net";
$fh = fopen($filename, "a"); //w is written from the beginning and a is appended
echo fwrite($fh, $word);
fclose($fh);
?>

Off topic, in the above example echo fwrite() displays a number. This number represents the length of the string

http://www.bkjia.com/PHPjc/890391.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/890391.htmlTechArticlePHP implements carriage return and line feed output in html source code. Enter line feed in the source code but does not display characters like br. We This needs to be achieved by escaping characters in PHP. Let’s take a look below. ...