javascript

How does JS get the selected value of the radio and not the selected value of the radio

The following is an article taken off the web (untested but very standard to imitate)


<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<title>text</title>
<script>
var chk = 0;
window.onload=function (){
var chkObjs = document.getElementsByName("radio");
for(var i=0;i<chkObjs.length;i++){
if(chkObjs[i].checked){
chk = i;
break;
}
}
}
function check_radio(){
var chkObjs = document.getElementsByName("radio");
for(var i=0;i<chkObjs.length;i++){
if(chkObjs[i].checked){
if(chk == i){
alert("radio No change in value can be committed ");
break;
}
}
}
}
</script>
</head>
<body>
<form action='' method='post' onsubmit='javascript:return check_radio()'>
<input type='radio' value='1' name='radio' checked='checked'> one ;
<input type='radio' value='2' name='radio'> two ;
<input type='radio' value='3' name='radio'> three ;
<input type='radio' value='4' name='radio'> four ;
<input type='radio' value='5' name='radio'> five ;

<input type=submit value=sub >
</form>
</body>
</html>

The following is to get the value of the radio without making a choice


<input type="radio" name="money" value="1" /> The dollar
<input type="radio" name="money" value="2" /> The Japanese yen
<input type="radio" name="money" value="3" /> The euro

Native JS mode :(native DOM manipulation treats text as a node, so there will be nextSibling)


var  The dollar  = document.getElementsByName("money")[0].nextSibling.nodeValue;
var  The Japanese yen  = document.getElementsByName("money")[1].nextSibling.nodeValue;
var  The euro  = document.getElementsByName("money")[2].nextSibling.nodeValue;

JQuery way


$('input[name="money"]:checked').next('span').html();

<input type="radio" name="money" value="1" checked="checked" /><span> The dollar </span>
<input type="radio" name="money" value="2" /><span> The Japanese yen </span>
<input type="radio" name="money" value="3" /><span> The euro </span>

<!-- Normally, creating checkboxes or checkboxes is used label Link it, for example: -->
<input id="radio1" type="radio" name="money" value="1" /><label for="radio1"> The dollar </label>

The following should be selected:

This one just determines if there is a choice


function radioValue(){
var radArr = document.getElementsByName("radiov");
var radValue = "";
//alert(radArr.length);
for(var i=0; i<radArr.length; i++){
//alert(radArr[i].checked+" "+radArr[i].name + " "+ radArr[i].value);
if(radArr[i].checked){
radValue = radArr[i].value;

}
}

if(radValue != null && radValue != ""){
alert(radValue);
}else{
alert(" Please select a ");
}

}

< Input type=“button” value=” get data from test radio “onclick=“radioValue();” / >