表格鼠標(biāo)懸停變色。代碼： var tr=document.getElementsByTagName('tr'); for (var i = 0; i < tr.length; i++) { tr[i].onmouseover=function(){
tr[i].style.backgroundColor="#f2f2f2";
} tr[i].onmouseleave=function(){ tr[i].style.backgroundColor="#fff";
}
}chrome說(shuō)的是 Uncaught TypeError: Cannot read property 'style' of undefined at HTMLTableRowElement.tr.(anonymous function).onmouseover但是把tr[i]改為this就可以: var tr=document.getElementsByTagName('tr'); for (var i = 0; i < tr.length; i++) {
tr[i].onmouseover=function(){ this.style.backgroundColor="#f2f2f2";
}
tr[i].onmouseleave=function(){ this.style.backgroundColor="#fff";
}
}
Js遍歷元素并賦予事件綁定匿名函數(shù)時(shí)，為什么調(diào)試說(shuō)未定義元素？
qq_笑_17
2018-10-10 18:15:55
