千鋒教育JavaScript全套視頻教程(10天學會Js,前端javascrip

閉包應(yīng)用場景之--閉包循環(huán)綁定事件:
html:
<button>1</button>
<button>2</button>
<button>3</button>
<button>4</button>
<button>5</button>
js:
var btns = document.querySelectorAll('button')
for (var i = 0; i < btns.length; i++) {
btns【i】.onclick = (function(index){
// var index = i
console.log(index)
return function(){
// console.log(456)
console.log(index)
}
})(i)
}
標簽: