Several useful php string filtering and conversion function code

Several useful php string filtering and conversion functions, mainly including security processing of some characters and string processing nl2br (); // \ n

Addslashes (); stripslashes (); // Escape Special characters when operating on the database

Chop (); // remove the right space of the string
Trim (); // remove all spaces in the string
Ltrim (); // remove the left space of the string

Htmlspecialchars (); // converts '$', '"', '<', '>' to the corresponding html entity
Htmlentities (); // Convert all html tags to corresponding html entities

Array explode (string separator, string str); // splits the string
String implode (string separator, array arr); // connection string

Strtoupper (); strtolower (); // converts the case sensitivity
Ucfirst (); // only converts the first character to uppercase.
Ucwords (); // converts the first letter of each word to uppercase.