README.md

#FunctionInject

Inject your script to any function before or after this function execute, or inject your script to any function's callback. ##Feature

• You can catch function's argument before execute, catch function's result after execute and before it's invoke function get it.
• You can change function's(and callback function) argument and result.
• You can cancel function execute.

##Sample define a function named setFullName, get a fullName argument, print it, use as callback's argument and return it.

var funcInject = require("./script/funcInject");
var callbackInject = require("./script/callbackInject");
var mouse = function(){};
mouse.prototype.setFullName = function(fullName, callback){
    this.fullName = fullName;
    console.log(this.fullName);
    if(callback instanceof Function){
        callback(this.fullName);
    }
    return this.fullName;
};

###preInject ####1. execute custom script before the function execute

funcInject.funcPreInject(mouse, 'setFullName',function(){
        console.log('injected');
    });
var mickey = new mouse();
console.log('result:' + mickey.setFullName('mickey mouse'));

####2. change the argument before the function execute

funcInject.funcPreInject(mouse, 'setFullName', function(fullNameObj){
    console.log('injected');
    fullNameObj.value = 'McDuck';
});
var mickey = new mouse();
console.log('result:' + mickey.setFullName('mickey mouse'));

####3. execute script and cancel execute the function's script execute custom script, return custom result and calcel execute the function's script

funcInject.funcPreInject(mouse, 'setFullName', function(fullNameObj){
        console.log('injected');
        return 'Goofy';
    });
var mickey = new mouse();
console.log('result:' + mickey.setFullName('mickey mouse'));

###sufInject ####1. get function's result value

funcInject.funcSufInject(mouse, 'setFullName', function(resultObj){
        console.log('injected, result:' + resultObj.value);
    });
var mickey = new mouse();
console.log('result:' + mickey.setFullName('mickey mouse'));

####2. change function's result change the function's result value before function's invoker get it

funcInject.funcSufInject(mouse, 'setFullName', function(oldResult){
    console.log('Injected');
    oldResult.value = 'McDuck'
});
var mickey = new mouse();
console.log('result:' + mickey.setFullName('mickey mouse'));

###callbackInject ‼️now target function's last argument as callback function(if it's type of Function)

####1. execute script before callback invoke your can execute custom script before the function's invoker callback function invoke

callbackInject.inject(mouse, 'setFullName', function(fullNameObj){
    console.log('Injected callback argument:'+ fullNameObj.value);
});
var mickey = new mouse();
console.log('result:' + mickey.setFullName('mickey mouse',function(fullName){
    console.log('callback argument:'+ fullName);
}));

####2. change callback's arguments

callbackInject.inject(mouse, 'setFullName', function(fullNameObj){
    console.log('Injected callback argument:'+ fullNameObj.value);
    fullNameObj.value = 'McDuck';
});
var mickey = new mouse();
console.log('result:' + mickey.setFullName('mickey mouse',function(fullName){
    console.log('callback argument:'+ fullName);
}));

TOTO:

• mutil callback support