Javascript pass variable value from one function to another

Question

I need to pass the value 7 as a parameter whenever i call check_scroll() function.

But now the lastcount value keeps on increasing even though i call check_scroll() function.

Please keep me some suggestion.

Check the code snippet as like i say,

first click on the first click me to initiate check_scroll function button, then scroll inside the div , you get an alert with value incrementing by 7.

Then click the button and then again scroll, but now the alert wont start from 7.

  $("#mybutton").click(function() { check_scroll(7); }) function check_scroll(val) { var lastcount = val; $('#notification_ul').scroll(function() { if ($('#notification_ul').scrollTop() + $('#notification_ul').innerHeight() == $('#notification_ul')[0].scrollHeight) { $("#notification_ul").append("<br/> Some Text Append <br/>"); alert(lastcount); lastcount = lastcount + 7; } }) } 

 div { width: 200px; height: 200px; overflow: auto; } 

 <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <div id="notification_ul"> Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book. It has survived not only five centuries, but also the leap into electronic typesetting, remaining essentially unchanged. It was popularised in the 1960s with the release of Letraset sheets containing Lorem Ipsum passages, and more recently with desktop publishing software like Aldus PageMaker including versions of Lorem Ipsum. </div> <button id="mybutton"> first click me to initiate check_scroll function </button> 

Answer 1

• define scroll event only once
• move lastcount to outside
• when the button is clicked, reset lastcount

$(function(){
    var lastcount = 0;

    $("#mybutton").click(function() {
        check_scroll(7);
    });

    $('#notification_ul').scroll(function() {
        if (lastcount !== 0) {
            if ($('#notification_ul').scrollTop() + $('#notification_ul').innerHeight() == $('#notification_ul')[0].scrollHeight) {
                $("#notification_ul").append("<br/> Some Text Append <br/>");
                console.log(lastcount);
                lastcount = lastcount + 7;
            }
        }
    });
});

function check_scroll(val) {
    lastcount = val;
}

Answer 2

Final Answer after referring your suggestions, Thanks you guys for the fast solution and suggestion. Thumbs Up

 var lastcount = 7; $("#mybutton").click(function() { check_scroll(7); }) $('#notification_ul').scroll(function() { if ($('#notification_ul').scrollTop() + $('#notification_ul').innerHeight() == $('#notification_ul')[0].scrollHeight) { $("#notification_ul").append("<br/> Some Text Append <br/>"); alert("last count after scroll " + lastcount); lastcount = lastcount + 7; } }) function check_scroll(val) { lastcount = val; alert("Last count reseted to " + lastcount); } 

 div { width: 200px; height: 200px; overflow: auto; } 

 <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <div id="notification_ul"> Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book. It has survived not only five centuries, but also the leap into electronic typesetting, remaining essentially unchanged. It was popularised in the 1960s with the release of Letraset sheets containing Lorem Ipsum passages, and more recently with desktop publishing software like Aldus PageMaker including versions of Lorem Ipsum. </div> <button id="mybutton"> sometext </button>