<!DOCTYPE?html>
<html>
?<head>
??<title>?new?document?</title>??
??<meta?http-equiv="Content-Type"?content="text/html;?charset=utf-8"/>???
??<script?type="text/javascript">?
??
??????window.onload?=?function(){
??????????????????
?????//?鼠標(biāo)移動(dòng)改變背景,可以通過給每行綁定鼠標(biāo)移上事件和鼠標(biāo)移除事件來改變所在行背景色。
????????var?trs=document.getElementsByTagName("tr");
????????console.log(trs);
????????for(var?i=0;i<trs.length;i++){
???????? ????????console.log(i);
???????? trs[i].setAttribute("onmouseover","msover(this)");
???????? trs[i].setAttribute("onmouseout","msout(this)");
????????}
????????
??????????var?as=document.getElementsByTagName("a");
????????????????for(var?i=0;i<as.length;i++){
???????????????? if?(as[i].innerHTML="刪除"){
???????????????? ????????as[i].setAttribute("onclick","this.parentNode.parentNode.parentNode.removeChild(this.parentNode.parentNode)");
???????????????? }
????????????????}
????????????????
??????????var?newlines?=?document.getElementsByTagName("input");
??????????for(var?i=0;i<newlines.length;i++){
???????????????? if?(newlines[i].value="添加一行"){
???????????????? newlines[i].setAttribute("onclick","addline()")
???????????????? }
??????????????}
???
?}
??????????
?????????function?addline(){
???????????????? var?newl?=?document.createElement("tr");
???????????????? newl.appendChild(document.createElement("td"));
???????????????? newl.appendChild(document.createElement("td"));
???????????????? var?tda?=?newl.appendChild(document.createElement("td"));
???????????????? newa=?document.createElement("a");
???????????????? newa.href="javascript:void(0);";
???????????????? newa.innerHTML="delrow";
???????????????? newa.setAttribute("onclick","this.parentNode.parentNode.remove();");
???????????????? tda.appendChild(newa);
???????????????? document.getElementsByTagName("tbody")[0].appendChild(newl);
???????????????? }
??????//?編寫一個(gè)函數(shù)，供添加按鈕調(diào)用，動(dòng)態(tài)在表格的最后一行添加子節(jié)點(diǎn)；
??????
????
??? ??
?????//?創(chuàng)建刪除函數(shù)
??</script>?
??
?</head>?
?<body>?
???<table?border="1"?width="50%"?id="table">
???<tr>
<th>學(xué)號(hào)</th>
<th>姓名</th>
<th>操作</th>
???</tr>??
???<tr>
<td>xh001</td>
<td>王小明</td>
<td><a?href="javascript:;"?>刪除</a></td>???<!--在刪除按鈕上添加點(diǎn)擊事件??-->
???</tr>
???<tr>
<td>xh002</td>
<td>劉小芳</td>
<td><a?href="javascript:;"?>刪除</a></td>???<!--在刪除按鈕上添加點(diǎn)擊事件??-->
???</tr>??
???</table>
???<input?type="button"?value="添加一行"??/>???<!--在添加按鈕上添加點(diǎn)擊事件??-->
???
??<script?type="text/javascript">? ???
???function?msover(x){
????? x.style.backgroundColor?=?"#ffffff";
?????}
?????function?msout(x){
????? x.style.backgroundColor="#F2F2F2";
?????}
?????</script>?
???
???
?</body>
?
?
</html>為啥我這里的 msover() msout() 方法必須寫在 body 里才能運(yùn)行，而寫在 head里的window.onload里就無法運(yùn)行呢？
為啥我的兩個(gè)方法必須寫在 body 里才能運(yùn)行，而寫在 head里就無法運(yùn)行呢？
qq_龐四_0
2016-09-20 00:38:37
