Php uses regular expressions to extract characters in string brackets, Parentheses, brackets, and braces

PHP uses regular expressions to extract character examples in string angle brackets <>, Parentheses (), brackets [], and braces {}. For more information, see

 

The Code is as follows:

$ Str = "Hello <I> (love) [BEIJING] {Tiananmen Square }";

 

Echo f1 ($ str); // return hello

Echo f2 ($ str); // return me

Echo f3 ($ str); // returns love

Echo f4 ($ str); // return to Beijing

Echo f5 ($ str); // return to Tiananmen

 

Function f1 ($ str)

{

$ Result = array ();

Preg_match_all ("/^ (.*)(? : <)/I ", $ str, $ result );

Return $ result [1] [0];

}

 

Function f2 ($ str)

{

$ Result = array ();

Preg_match_all ("/(? : <)(.*)(? :>)/I ", $ str, $ result );

Return $ result [1] [0];

}

 

Function f3 ($ str)

{

$ Result = array ();

Preg_match_all ("/(? :\()(.*)(? : \)/I ", $ str, $ result );

Return $ result [1] [0];

}

 

Function f4 ($ str)

{

$ Result = array ();

Preg_match_all ("/(? :\[)(.*)(? : \])/I ", $ str, $ result );

Return $ result [1] [0];

}

 

Function f5 ($ str)

{

$ Result = array ();

Preg_match_all ("/(? :\{)(.*)(? :\})/I ", $ str, $ result );

Return $ result [1] [0];

}

 

 

 

PS :(? : Character) indicates that this character is not captured. It seems that PHP does not support replacing characters with parentheses.

Otherwise, you can view the loop as nested, and then perform loop matching.

PS2: Huanshi :(?!) (? = )(? <!) (? <=)

If there is a smaller number, match on the right, and if not, match on the left. Exclamation points indicate unequal, and equal signs indicate equal.

PS3: all are verified by the validators. For more information about the validators, see references.