angular源码分析之bind函数

angular.bind函数分析

解释：返回一个调用self的函数fn（self代表fn里的this）.可以给fn提供参数args.这个功能也被称为局部操作，以区别功能.
格式：angular.bind(self,fn,args);
self：object 对象； fn的上下文对象，在fn中可以用this调用
fn：function； 绑定的方法

var obj = { name: "Any" };
var fn = function (Adj) {
  console.log(this.name + "is a boy!!! And he is " + Adj + " !!!");
};
var f = angular.bind(obj, fn, "handsome");
f();//Any is a boy!!! And he is handsome!!!
var t = angular.bind(obj, fn);
t("ugly");// Any is a boy!!! And he is ugly!!!

上源码:

function concat(array1, array2, index) {
  return array1.concat(slice.call(array2, index));
}

function sliceArgs(args, startIndex) {
  return slice.call(args, startIndex || 0);
}

function bind(self, fn) {
var curryArgs = arguments.length > 2 ? sliceArgs(arguments, 2) : [];
//判断是否是函数 且不能是正则类型
if (isFunction(fn) && !(fn instanceof RegExp)) {
  return curryArgs.length
    ? function() {
        return arguments.length
          ? fn.apply(self, concat(curryArgs, arguments, 0))
          : fn.apply(self, curryArgs);
      }
    : function() {
        return arguments.length
          ? fn.apply(self, arguments)
          : fn.call(self);
      };
} else {
  // In IE, native methods are not functions so they cannot be bound (note: they don't need to be).
  return fn;
}
}