在需要调用n次数后调用回调时,请使用它.
var fn = _.after(3, function () {
console.log('done');
});
fn(); // Nothing
fn(); // Nothing
fn(); // Prints "done"
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所有异步调用完成后调用回调非常有用.
var done = _.after(3, function () {
console.log('all 3 requests done!');
});
$.get('https://example.com', done);
$.get('https://example.com', done);
$.get('https://example.com', done);
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射击3次后球员死亡的基本游戏示例.
var isDead = _.after(3, function () {
console.log('Player died!');
});
player1.shoot(player2, isDead); // undefined
player1.shoot(player2, isDead); // undefined
player1.shoot(player2, isDead); // "Player died!"
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基本上你用来_.after代替手动计数器.