CODEWITHSUNDEEP
javascriptfunctionvariablescall
Maria
Maria

Reputation: 3525

javascript: get a function's variable's value within another function

okay so I have this code in body:

<input type="text" value="haha" id="full_name"/>

And this code in script

<script language="javascript" type="text/javascript">
    function first(){
        var nameContent=document.getElementById('full_name').value;
    }

    function second() {
        first();
        y=nameContent; 
        alert(y);
    }
    second();
</script>

I want a alert showing the value of the element full_name, but it doesn't seem to work, does anyone know why? :S

Upvotes: 18

Views: 138315

Answers (5)

Ricardo Mendoza
Ricardo Mendoza

Reputation: 1

the OOP way to do this in ES5 is to make that variable into a property using the this keyword.

function first(){
    this.nameContent=document.getElementById('full_name').value;
}

function second() {
    y=new first();
    alert(y.nameContent);
}

Upvotes: 0

The Alpha
The Alpha

Reputation: 146191

Your nameContent variable is inside the function scope and not visible outside that function so if you want to use the nameContent outside of the function then declare it global inside the <script> tag and use inside functions without the var keyword as follows

<script language="javascript" type="text/javascript">
    var nameContent; // In the global scope
    function first(){
        nameContent=document.getElementById('full_name').value;
    }

    function second() {
        first();
        y=nameContent; 
        alert(y);
    }
    second();
</script>

Upvotes: 1

Jason Fingar
Jason Fingar

Reputation: 3372

you need a return statement in your first function.

function first(){
    var nameContent = document.getElementById('full_name').value;
    return nameContent;
}

and then in your second function can be:

function second(){
    alert(first());
}

Upvotes: 1

Marcelo Assis
Marcelo Assis

Reputation: 5194

Your nameContent scope is only inside first function. You'll never get it's value that way.

var nameContent; // now it's global!
function first(){
    nameContent = document.getElementById('full_name').value;
}

function second() {
    first(); 
    y=nameContent; 
    alert(y);
}
second();

Upvotes: 4

Blender
Blender

Reputation: 298176

nameContent only exists within the first() function, as you defined it within the first() function.

To make its scope broader, define it outside of the functions:

var nameContent;

function first(){
    nameContent=document.getElementById('full_name').value;
}

function second() {
    first();
    y=nameContent; alert(y);
}
second();

A slightly better approach would be to return the value, as global variables get messy very quickly:

function getFullName() {
  return document.getElementById('full_name').value;
}

function doStuff() {
  var name = getFullName();

  alert(name);
}

doStuff();

Upvotes: 20

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