javascript 从下拉列表中动态选择值
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dynamically select value from drop down list
提问by Kim
I have the following drop down list:
我有以下下拉列表：
<select name="selSS1" id="select_value">
<option value="val0">sea zero</option>
<option value="val1">sea one</option>
<option value="val2">sea two</option>
<option value="val3">sea three</option>
<option value="val4">sea four</option>
</select>
I would like to dynamically select a value from that list using javascript:
我想使用 javascript 从该列表中动态选择一个值：
I tried:
我试过：
document.getElementById('select_value').selected ="val3";
But the above code does not seem to work. Any help is most appreciated.
但是上面的代码似乎不起作用。非常感谢任何帮助。
回答by AmGates
Use the following line:
使用以下行：
document.getElementById('select_value').value ="val3";
or
document.getElementById('select_value').selectedIndex = 3;
Hope this solves ur problem.
希望这能解决你的问题。
回答by Pratik Bhatt
$('#select_value').val('val0');
回答by Bogdan Emil Mariesan
With plain JavaScript:
使用纯 JavaScript：
var element = document.getElementById("select_value");
var selectedValue = element.options[element.selectedIndex].value;
回答by Th0rndike
try:
尝试：
var mySelect = document.getElementById('select_value');
mySelect.getElementsByTagName('option')[index].setAttribute('selected','selected');
where index stands for the position of the option you want to select.
其中 index 代表您要选择的选项的位置。
回答by Rafael Marques
Try it this way:
试试这个方法：
document.getElementById('select_value').option[3].selected;
document.getElementById('select_value').option[3].selected;
回答by Kunal Vashist
THis will select val 3
这将选择 val 3
document.getElementById('select_value').selectedIndex=3;
回答by Javier Cobos
If you want to set the selected one by the value, try this function. By declaring a function you will be able to use this functionality with any select :).
如果您想通过值设置选定的一个，请尝试此功能。通过声明一个函数，您将能够将此功能与任何选择一起使用 :)。
// Simplest version
// 最简单的版本
function setSelected(select_id,value){
document.getElementById(select_id).value = value;
}
// Or, complex version
// 或者，复杂版本
function setSelected(select_id,value){
var mySelect = document.getElementById(select_id);
var options = mySelect.options;
var key;
for(key in options){
if(options[key].value===value){
options[key].setAttribute("selected","");
}
else
options[key].removeAttribute("selected");
}
}
in your case:
在你的情况下：
setSelected("select_value","val3");
