Write js var without refresh

Question

So lets say the var x = 5, and you do document.write(x); but then later do var x = 7, how do you update the document.write to say 7?

Answer 1

It depends on how you change the x value, for example:

---------------------------------------

// Variable
var x = 5;

// Value change every 200ms
setInterval(function(){
document.write('Variable is: ' + x++ + '<br>' )
},200)

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document.write( ) must be used for testing purposes only, so... don't use it!
Create a paragraph and put inside it values with the innerHTML property, is definitely easier for change a value dynamically. ;)

Answer 2

var params = {
_x : 5,
get x(){ return this._x; },
set x(value){
this._x = value;
document.write(value);
}
};

params.x = 7; //writes 7 into document;
params.x = 666; //writes 666 into document;
console.log(params.x) //outputs 666 into console