How to put maximum limit in a javascript?

Here is the part of my form that uploads multiple images. It has an add more button, that opens a new input field. Whenever the user clicks on add more button, one new input field is opened. However, I wish that after the 5th input field is opened, and the user clicks on add more again, no new field should get open (ie I wish to limit the size of input field to 5)

<div id="formdiv">
    <form enctype="multipart/form-data" action="" method="post">
        <div id="filediv"><input name="file[]" type="file" id="file"/></div><br/>
            <input type="button" id="add_more" class="upload" value="Add More Files"/>
            <input type="submit" value="Upload File" name="submit" id="upload" class="upload"/>
    </form>
</div>

javascript that handles the working

var abc = 0; //Declaring and defining global increement variable

$(document).ready(function() {

//To add new input file field dynamically, on click of "Add More Files" button below function will be executed
    $('#add_more').click(function() {
        $(this).before($("<div/>", {id: 'filediv'}).fadeIn('slow').append(
                $("<input/>", {name: 'file[]', type: 'file', id: 'file'}),        
                $("<br/><br/>")
                ));
    });

//following function will executes on change event of file input to select different file   
$('body').on('change', '#file', function(){
            if (this.files && this.files[0]) {
                 abc += 1; //increementing global variable by 1

                var z = abc - 1;
                var x = $(this).parent().find('#previewimg' + z).remove();
                $(this).before("<div id='abcd"+ abc +"' class='abcd'><img id='previewimg" + abc + "' src=''/></div>");

                var reader = new FileReader();
                reader.onload = imageIsLoaded;
                reader.readAsDataURL(this.files[0]);

                $(this).hide();
                $("#abcd"+ abc).append($("<img/>", {id: 'img', src: 'img/x.png', alt: 'delete'}).click(function() {
                $(this).parent().parent().remove();
                }));
            }
        });

//To preview image     
    function imageIsLoaded(e) {
        $('#previewimg' + abc).attr('src', e.target.result);
    };

    $('#upload').click(function(e) {
        var name = $(":file").val();
        if (!name)
        {
            alert("First Image Must Be Selected");
            e.preventDefault();
        }
    });
});

Can anyone help me in applying this maximum limit?

---

You need to set a counter acheive this. you can update your code as follows.

var count=0;

  $('#add_more').click(function() {

if(count<5)
{
        $(this).before($("<div/>", {id: 'filediv'}).fadeIn('slow').append(
                $("<input/>", {name: 'file[]', type: 'file', id: 'file'}),        
                $("<br/><br/>")
                ));
count++;

 } 
  });

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