將參數傳遞給回調函數

Question

默認情況下，我無法將參數傳遞給回調函數

 function callback() { alert('Hi human'); } var x = 1, y = 2;//Pass arguments(x,y) to a callback function document.getElementById('someelem').addEventListener('click', callback); 

 <button id="someelem">Ok</button> 

Answer 1

document.getElementById('someelem').addEventListener('click', function(event) {
    callback(x, y, e);
});

另一種方法是綁定功能

document.getElementById('someelem').addEventListener('click', callback.bind(null, x, y));

Answer 2

您可以將其創建為匿名函數，如下所示：

var x = 1, y = 2;//Pass arguments(x,y) to a callback function

document.getElementById('someelem').addEventListener('click', function(x, y) {
   alert('Hi human');
});

Answer 3

您可以使用bind來解決此問題。

 function callback(x, y) { console.log(this,x,y); } var x = 1, y = 2; //Pass arguments(x,y) to a callback function var el = document.getElementById('someelem'); el.addEventListener('click', callback.bind(el, x, y)); 

 <button id="someelem">OK</button>