


Summary of four security filtering functions in PHP (with code)
This article introduces to you a summary of the four security filtering functions in PHP (with code). It has certain reference value. Friends in need can refer to it. I hope it will be helpful to you.
1. Stripslashes() function
The main function of stripslashes() is to delete backslashes
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Output result:
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2. htmlentities() function
htmlentities() converts characters into HTML entities
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The HTML output of the above code is as follows (view source code):
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Browser output of the above code:
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3, htmlspecialchars() function
Convert the predefined characters "<" (less than) and " >" (greater than) converted to HTML entity:
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The HTML output of the above code is as follows (view source code):
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The browser output of the above code:
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4. strip_tags() function
Strips the HTML tags in the string:
strip_tags() function strips the HTML, XML and PHP in the string Label.
Comments: This function always strips HTML comments. This cannot be changed via the allow parameter.
Note: This function is binary safe.
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