PHP addslashes () function specific application parsing _php tutorial

We pass onDefinition and usage
The Addslashes () function adds a backslash before the specified predefined character.

These predefined characters are:

Single quotation mark (')
Double quotation marks (")
Back slash ()
Null

Grammar
C

Parameter description
string is required. Specifies the string to check.

Hints and Notes
Tip: This function can be used to prepare the appropriate string for strings stored in the database and for database query statements.

Note: By default, PHP instruction MAGIC_QUOTES_GPC is on, and automatically runs Addslashes () for all GET, POST, and COOKIE data. Do not use Addslashes () for strings that have been MAGIC_QUOTES_GPC escaped, because this results in double-layer escaping. You can use the function GET_MAGIC_QUOTES_GPC () to detect this situation.

Example

In this case, we're going to add a backslash to the predefined string:

 
  
  

  
   
   
< ? PHP 
  
   
   
$ Str  "who ' s John Adams?" ; 
  
   
   
Echo $str. "This was not safe in a database query.
  
   
   
<br/>"; 
  
   
   
echo addslashes ($STR). "This is safe in a database query."; 
  
   
   
?>
 
  
  

Output:

Who ' s John Adams? This is the not safe in a database query.
Who ' s John Adams? This is safe in a database query.

An example of using addslashes () is when you want to enter data into the database. For example, the name O ' Reilly is inserted into the database, which needs to be escaped. Most databases are used as escape characters: O ' Reilly. This allows the data to be placed in the database without inserting additional. When PHP instruction Magic_quotes_sybase is set to ON, it means that the insert ' will be used ' to escape.

By default, PHP instruction MAGIC_QUOTES_GPC is on, and it is primarily for all GET, POST, and COOKIE data automatically run Addslashes (). Do not use Addslashes () for strings that have been MAGIC_QUOTES_GPC escaped, because this results in double-layer escaping. You can use the function GET_MAGIC_QUOTES_GPC () to detect this situation.

http://www.bkjia.com/PHPjc/446258.html www.bkjia.com true http://www.bkjia.com/PHPjc/446258.html techarticle we add a backslash before the specified predefined character by using the Addslashes () function for the definition and usage. These predefined characters are: Single quotation mark (') Double quotation mark (") backslash () NULL syntax ...

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