How does JavaScript get the value in the check box?

Idea: Get the checkbox object → loop checkbox array, judging by the checked property whether to select → Use the Value property to get the value of the selected item. The example shows the following:

1. HTML structure

<form>    <input type= "checkbox" Name= "IDs" value= "1"/>    <input type= "checkbox" Name= "IDs" value= "2"/>    <input type= "checkbox" Name= "IDs" value= "3"/>    <input type= "button" value= "Show" onclick= " GetIDs () "/></form>

2. JavaScript code

function GetIDs () {    var ids = Document.getelementsbyname ("IDs");     var str = [];      for (i=0;i<ids.length;i++) {        if(ids[i].checked) {            str.push (ids[i].value);        }    }    Console.log (str);}

3. Effect Demonstration

How does JavaScript get the value in the check box?