如何从复选框中获取值

Question

here is my code. I can't make the alert works.

var chooseObject = document.getElementsByTagName("input");
var objectLength = chooseObject.length;
var hobbyArray = [];
    //hobbyArray("aaa");
    //hobbyArray("bbb");
    //alert(hobbyArray); This one works.
for(var i=0;i<=objectLength;i++){
    if((chooseObject[i].type=="checkbox")&&(chooseObject[i].checked==true)){
         //alert(chooseObject[i].value); This one works.
         hobbyArray.push(chooseObject[i].value); }
}
alert(hobbyArray);

If I do the top alert(I comment already) it works. If I alert chooseObject[i].value in the for loop, its fine. But if I do with array, it failed. Could someone help me?

Answer 1

You have a silly error on your for statement. This:

for(var i=0;i<=objectLength;i++)

should be:

for(var i=0;i<objectLength;i++)

The extra iteration is causing a TypeError when you check the element's properties ( chooseObject[objectLength] gives undefined , which has no properties).