How to Preprocess a get lost string data is safe

How to get the string data to be preprocessed before it is safe
Get to a string of characters and then want to put in the SQL where ' project ' =$_get[' xxxxx ' statement, and then find the information in MySQL
How to handle it safely

I want this string to get to only the numbers and the English letters left.

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Then you'll have to dispose of characters that are not letters and numbers.
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Http://www.w3school.com.cn/php/func_mysql_real_escape_string.asp

Http://www.w3school.com.cn/php/func_string_addslashes.asp

Custom Filtration Functions
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Reference:

Then you'll have to dispose of characters that are not letters and numbers.


Yes, yes, that's it.

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