异步对象传统写法?
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function aaa (callback) {
setTimeout(function () {
callback(5);
},1000);
}
function done (value) {
console.log(value);
}
aaa(function (value) {
done(value)
});
疑问? 为什么不这么写
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function aaa (callback) {
setTimeout(function () {
callback(5);
},1000);
}
function done (value) {
console.log(value);
}
aaa(done);
jq上的写法
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var defer = $.Deferred();
setTimeout(function () {
defer.resolve(5);
},1000);
var filtered = defer.then(function (value) {
return value * 2;
});
filtered.done(function (value) {
console.log('打印值',value);
})
减少回调函数的嵌套?逻辑扁平化?
