Implementation of the string. Format method in Javascript

In JavaScript, the string. Format method similar to the string. Format method in C # is implemented through prototype extension and regular expression.

Method implementation:

 

String. Prototype. Format =   Function (ARGs ){
VaR Str =   This ;
Return Str. Replace ( New Regexp ( " {-? [0-9] +} " , " G " ), Function (Item ){
VaR Intval = Parseint (item. substring ( 1 , Item. Length -   1 ));
VaR Replace;
If (Intval > =   0 ){
Replace = ARGs [intval];
} Else   If (Intval ===   - 1 ){
Replace =   " { " ;
} Else   If (Intval ===   - 2 ){
Replace =   " } " ;
} Else {
Replace =   "" ;
}
Return Replace;
});
};

Use:

VaR Str =   " She {1} {0} {2} By the {0} {3}. {-1} ^ _ ^ {-2} " ;
Str = Str. Format ([ " Sea " , " Sells " , " Shells " , " Shore " ]);
Alert (STR ); // Out put: She sells seashells by the seashore. {^ _ ^}

Original article address: String. format in Javascript