1、通过修改select的value值 1 <input type="button" id="btn" value="按钮"/> 2 <select name="select" id="select"> 3 <option value="1">aa</option> 4 <option value="a">bb</option> 5 <option value="c">cc</option> 6 </select> 7 <script type="text/javascript"> 8 //点击按钮...
//方式一:使用select元素的selectedIndex属性,selectedIndex是设置或获取选中选项(<option>)位于 select 对象中的位置 tagSelect.selectedIndex = selectIndex; /*方式二:使用select元素的options集合,options代表select元素中的所有<option>子标记, 如果需要访问options集合中的第二个option时,可以通过options[1]的方式访问;...
oSelectMonth.options.length = 0;//清空Select里面的options 三、设置默认选中option varoSelectMonth = document.getElementById("SelectMonth"); //oSelectMonth.selectedIndex = 1;//方法一:默认选中第二项 //setTimeout(function() { oSelectMonth.selectedIndex = 1; }, 0); //用setTimeout延迟是为了防...
<select multiple id="leftSel" onclick="setButton(this)" style="height:200px;width:100px;"> <option value="1">Java</option> <option value="2">JavaScript</option> <option value="3">C++</option> <option value="4">HTML</option> </select> </td> <td> <input type="button" value=...
因此,只需将您的密钥更改为唯一的,以标识列表中的项目 {DD2.map((x, i) => ( <option key={x.content} value={x.content}> {x.content} </option>))} 参考react关于select和option如何使用 你可以试试这样的 export default function App() { const [state, setState] = React.useState({ category...
Example: viewport: '#viewport' or { "selector": "#viewport", "padding": 0 } If a function is given, it is called with the triggering element DOM node as its only argument. The this context is set to the tooltip instance. Data attributes for individual tooltips Options for individual ...
vardom=document.getElementById("container");varmyChart=echarts.init(dom);varapp={};option=null;option={title:{text:'Large-scale scatterplot'},tooltip:{trigger:'axis',showDelay:0,axisPointer:{show:true,type:'cross',lineStyle:{type:'dashed',width:1}},zlevel:1},legend:{data:['sin','co...
// objSelect.add(objOption, objSelect.selectedIndex); } //--> </SCRIPT> </HEAD> <BODY onload="setProvinces()"> <!--Select.selectedIndex (Property) qixy: through experiment: Select.selectedIndex is 0-based.但是第0项是“请选择省份-- ” --> <select name="select" id="province" onchang...
Example: viewport: '#viewport' or { "selector": "#viewport", "padding": 0 } If a function is given, it is called with the triggering element DOM node as its only argument. The this context is set to the popover instance. sanitize boolean true Enable or disable the sanitization. If ...
The options.length property specifies the number of elements in the array, as does the select .length property. See the Option object for further details. In JavaScript 1.1, you can modify the options displayed in a Select object in any of the following ways: If you set options.length ...