The example in this article describes the JS method of obtaining the display value of the drop-down box and judging the radio button. Share it with everyone for your reference. The details are as follows:
1. I have done many projects, and I need to get the value displayed by the select component. Here are the methods I often use:
Html source code is as follows:
<html><body> <select id="province" name="province" > <option value="1">北京</option> <option value="2">上海</option> <option value="3">江苏</option> <option value="4">河北</option> </select> <br/> <input type="text" id="provinceName" name="provinceName"/> <input type="button" onClick="setTxt()" value="赋值"/> </body></html>
The JS function is as follows:
function setTxt()
{
var _selObj=document.getElementByIdx_xx('province');//取下拉框的元素
var _selVal=_selObj[_selObj.selectedIndex].text;//取下拉框被选中的值
document.getElementByIdx_xx('provinceName').value=_selVal;
}
2. I have done a lot of judging whether the radio button is selected. The following is the method I often use:
HTML page source code is as follows:
<html><body> <input type="radio" name="time" value="2009-05-20"/>2009-05-20 <input type="radio" name="time" value="2009-05-21"/>2009-05-21 <input type="radio" name="time" value="2009-05-22"/>2009-05-22 <input type="radio" name="time" value="2009-05-23"/>2009-05-23 <input type="button" value="判断是否选择" onclick="alert(judge())"/> </body></html>
JS function code:
function judge()
{ var status =false;
var _radObj=document.getElementsByName('time');
for(var i =0;i<_radObj.length;i++){
if(_radObj[i].checked){
status=true;
}
}
if(! status){
alert('未选中时间!');
}
return status;
}
I hope this article will be helpful to everyone’s JavaScript programming design.
![[Web front-end] Node.js quick start](https://img.php.cn/upload/course/000/000/067/662b5d34ba7c0227.png)
