Example of a PHP regular expression escape character

$str = Preg_quote ("/\d{3} (\-\d{4})/"); Echo $str; ?> Copy Code Results:/\\d\{3\}\ (\\\-\\d\{4\}\)/ Example 2: $str = Preg_quote ("/\d{3} (\-\d{4})/", "3"); Echo $str; ?> Copy Code Results:/\\d\{\3\}\ (\\\-\\d\{4\}\)/The difference between the two examples: "3" in the red area, and "3" in the second example. PHP escape character function php escape regular expression character function php form post argument automatically add escape character problem PHP anti-injection and form commit value escaped code in MySQL statement escape Method Example PHP character escapes related considerations

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