call
Function.prototype._call = function(targetObject) {
if (typeof targetObject === 'undefined' || targetObject === null) {
targetObject = window
}
targetObject = new Object(targetObject)
const targetFnKey = 'targetFnKey'
targetObject[targetFnKey] = this
const result = targetObject[targetFnKey](...[...arguments].slice(1))
delete targetObject[targetFnKey]
return result
}
apply
Function.prototype._apply = function(targetObject, argsArray) {
if (typeof argsArray === 'undefined' || argsArray === null) {
argsArray = []
}
if (typeof targetObject === 'undefined' || targetObject === null) {
targetObject = window
}
targetObject = new Object(targetObject)
const targetFnKey = 'targetFnKey'
targetObject[targetFnKey] = this
const result = targetObject[targetFnKey](...argsArray)
delete targetObject[targetFnKey]
return result
}
bind
Function.prototype._bind =
Function.prototype._bind ||
function(context) {
if (typeof this !== 'function') {
throw new Error('Function.prototype.bind -not function')
}
var self = this
//预设参数
var args = Array.prototype.slice.call(arguments, 1)
var F = function() {}
F.prototype = this.prototype
var fBind = function() {
var innerArgs = Array.prototype.slice.call(arguments)
var finalArgs = args.concat(innerArgs)
return self.apply(this instanceof F ? this : context, finalArgs)
}
fBind.prototype = new F()
return fBind
}
