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Closed 11 years ago.

哪些职能反馈结构最能用于贾瓦特,为什么? 我看到这两种选择都使用了许多。是否有其他东西?

Option A:

// DECLARATION
function funcA(required, success, error, options){

  // if there is an error in your function return 
  // and run error function
  if(errorHappens){ return error( an error ) };

  // if no error happened: run the success function
  success( all good here is your var back , required);
}

。

// USAGE
funcA( this is required , function(result){

  // all good, do something with the result :)

},
function(error){

  // tell the user about the error
  alert( error happened )  
},{
  optionalThing:  :-) 
});

Option B:

// DECLARATION
function funcB(required, callback, options){

  // if an error happens run the single callback with
  // the err param populated and return
  if(errorHappens){ return callback( an error ) };

  // if no error happened: run the callback with  null 
  // as the error param.
  callback(null,  this is a result );
}

.

// USAGE
funcB( this is required , function(err, result){
  if(err){ return alert( error happened ) };

  // all good do something with the result :)

},{
  optionalThing:  :-) 
}

Answer 1

这取决于环境。 j)

I would personally recommend you stick to callback as the last parameter

function doSomething(data, options, cb) {
  ...
  if (err) return cb(err);
  cb(null, result);
}

doSomething(data, { ... }, function (err, data) {
    if (err) throw err;
    ...
});

这主要是因为这种 co式习惯在de社区使用。如果你不与点子互动。 j 毕竟,你或许应该使用你与我们重新互动的环境最常见的风格。

如果你的环境主要围绕 j,那么我就只回下一张<条码>美元。递延从<条码>中删除

function doSomething(data, options) {
  return $.Deferred();
}

$.when(
  doSomething(data, { ... })
).then(
  function () { /* success */ },
  function () { /* error */ }
);

Edit:

function doSomething(data, options, cb) {
  if (typeof options === "function") {
    cb = options;
    options = null;
  }
  ...
}

Answer 2

It doesn t really matter what you pick. I d prefer B because I can add more error codes without changing the function definition.

You can also use the another pattern where your callback is a hash of functions {error: function(){}, success: function(){}}. And this is extensible and quite common in JS libraries.

Answer 3

我倾向于通过字面字面字面,即:

var callback = {
    success : function(){},
    error : function(){},
    complete : function(){}
};

以这种方式使用:

function(callback){
    try{
        /*...processing...*/
        if(success)
            typeof callback.success ===  function  && callback.success(result);
        else 
            throw new Error( unsuccesfull );
    }catch(err){
        typeof callback.error ===  function  && callback.error(err.message);
    }finally{
        typeof callback.complete ===  function  && callback.complete() || typeof callback ===  function  && callback();
    }
}

主要好处是,以这种方式,我可以对每一种结果状况发出呼吁,但我也可以放弃我所希望的任何地位倒退。我甚至可以仅通过一个功能(而不是一个物体),该功能相当于<代码>complete。

Answer 4

也没有。

我更喜欢一个充满论点的全称版本,而采用“共同”观点的简短方法作为参数。

最有意义的是取决于有关职能的使用模式。

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