如何从JavaScript更新隐藏字段值

Question

I have a JSP page where I Select 5 item rows. I am adding the Select Id s in sdata array. I added a hidden button. alert is showing the full list. How can I set this list to the hidden field's( mids ) value?

<input type="hidden" name="mids" value="">

JavaScript:

$( document ).ready(function() {

var sdata =new Array();

  fn-create-ids{
     (checckbox.each.check())
      {
        sdata.push(i);
      }
      document.GetelementbyName("mids").value=sdata;
      alert(document.GetelementbyName("mids").value);---shows value
   }
 If I add it here, it is empty
 document.GetelementbyName("mids").value=sdata;---empty
} 

Answer 1

Give these hidden fields some ids

and then use

document.getElementById('hiddenfieldID').value +="your value";

in javascript

Example :

  document.getElementById('mid').value += sdata;

BUT

Really didn't understand how this function works

fn-create-ids{
     (checckbox.each.check())
      {
        sdata.push(i);
      }
   }

i think the value should be i

document.getElementById('mid').value +=i;

Answer 2

Sajad's answer is valid, but if you want to keep using just names, here's how. (You may already have a form in your document; if so, then just use the existing 'name' attribute for the Javascript)

<form name="midsForm">
  <input type="hidden" name="mids" value="">
</form>

Then:

document.forms.midsForm.mids.value = "your value";

Answer 3

I have a header column which is a Checkbox(parent-check). Dynamically, I am filling bottom rows. Now when I select "parent-check", it is selecting all 13 rows that come from db. I have a submit button at the bottom outside of my display tag. when I click submit, I am going to another page. I will Select the check box(parent-check) to select all rows and then I will click submit. By this time, I want javascript to update my hidden field value with the array that will contain all selected row ids. Jsp: In my existing script, I found this:

$(document).ready(function() {

var sdata =new Array();

  $("#parent-check").click(function() {
     if ($(this).prop("checked")) {
        $("td>:checkbox").each(function() {
            sdata.push($(this).attr("mids");
        });
      }
      document.GetelementbyName("mids").value=sdata;
      alert(document.GetelementbyName("mids").value);---shows value
   }
 If I add it here, it is empty
 document.GetelementbyName("mids").value=sdata;---empty
} 

Answer 4

It is getting the array list inside a function. But the list becomes empty when I come out of the function though I declare it outside of the function under $( document ).ready(function().