[b]htmlspecialchars[/b]
(PHP 3, PHP 4 )

把html语言的特殊标记变成转义的符号
htmlspecialchars -- Convert special characters to HTML entities
Description
string htmlspecialchars ( string string [, int quote_style [, string charset]])


'&' (ampersand) becomes '&'

'"' (double quote) becomes '"' when ENT_NOQUOTES is not set.

''' (single quote) becomes ''' only when ENT_QUOTES is set.

'<' (less than) becomes '<'

'>' (greater than) becomes '>'

例子 1. htmlspecialchars() example

[code]
$new = htmlspecialchars("Test", ENT_QUOTES);
echo $new; // <a href='test'>Test</a>
?>

[b]htmlentities[/b]
(PHP 3, PHP 4 )

htmlentities -- Convert all applicable characters to HTML entities
与前一个函数相同，但是他是把所有的字符转换了

[b]nl2br[/b]
(PHP 3, PHP 4 )

nl2br -- Inserts HTML line breaks before all newlines in a string
字符串中有换行标记的转换成html 的

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