Hi im new and noob

memo333

10-10-2012, 07:38 PM

Im programming a dice and coin randomizer, but I cant make the coin works

this is html with js all in one, when I press the TIRA MONEDA button it says undefined...I know its a varible but im clueless plz help :);)

<!DOCTYPE html>
<html>
<head>
<script>

/*
gaga
*/
//random coin
//preload the six images first
var face0=new Image()
face0.src="d1.gif"
var face1=new Image()
face1.src="d2.gif"
var face2=new Image()
face2.src="d3.gif"
var face3=new Image()
face3.src="d4.gif"
var face4=new Image()
face4.src="d5.gif"
var face5=new Image()
face5.src="d6.gif"
</script>
<img src="d1.gif" name="mydice">
<form>
<input type="button" value="Throw dice!" onClick="throwdice()">
<p>
<input type="button" value="TIRA MONEDA!" onClick="sayHello()">
<div id="result"></div>
<script>

function sayHello(){
document.getElementById("result").innerHTML = throwcoin();

}

/*function sayHello(name){
document.getElementById("result").innerHTML = 'Hello ' + name + '!';

}*/

function throwdice(){
//create a random integer between 0 and 5
var randomdice=Math.round(Math.random()*5)
document.images["mydice"].src=eval("face"+randomdice+".src")
}

function throwcoin(){
//create a random integer between 0 and 1
//this.randomcoin=Math.round(Math.random()*1)
this.randomcoin=1;
if(randomcoin===0){return document.getElementById("result").innerHTML = throwcoin.randomcoin;
}
else{return document.write('AGUILA!')}
}
</script>
<title>MEMO MATH TEST</title>
</head>
<body>

<div id="border2">
</div>
</body>
</html>

VIPStephan

10-11-2012, 12:59 AM

If you post any code please put it in between tags. It makes scanning your posts much easier. You can do this by clicking the small ‘#’ icon above the reply field. Also, in the future, please use a more descriptive subject when posting a question. See posting guidelines. (http://www.codingforums.com/postguide.htm)

Old Pedant

10-11-2012, 01:51 AM

This is a killer:

else{return document.write('AGUILA!')}

You CAN NOT use document.write once a page is loaded. Doing so WIPES OUT the page, including even the JS code that did the document.write.

As your code stands, once you hit that button, your page is GONE!

There are lots of other things wrong in that code.

You code to get a random number is all wrong. *NEVER* use Math.round() when getting a random integer.

The correct code is:

var random = Math.floor( Math.random() * numberOfChoices );

So for dice you would use

var randomdice = Math.floor( Math.random() * 6 );

That will get you *GOOD* random numbers from 0 to 5. Just add 1 to get numbers from 1 to 6.

Your HTML is totally illegal. ALL this code
<img src="d1.gif" name="mydice">
<form>
<input type="button" value="Throw dice!" onClick="throwdice()">
<p>
<input type="button" value="TIRA MONEDA!" onClick="sayHello()">
<div id="result"></div>

needs to be BETWEEN <body> and </body>. Oh, and you are missing the </form> tag.

Use of document.images[ ] is obsolescent. Just give your images an id and then use document.getElementById().

*NEVER* use eval(). Expecially when there is NO NEED WHATSOEVER, as in this case.

Old Pedant

10-11-2012, 01:56 AM

Here, try this:

<!DOCTYPE html>
<html>
<head>
<script type="text/javascript">
//random coin
//preload the six images first
var dice = [];
for ( var i = 1; i <= 6; ++i )
{
var d = new Image();
d.src = "d" + i + ".gif";
dice[i] = d;
}

function sayHello(){
document.getElementById("result").innerHTML = throwcoin();

}

function throwdice(){
//create a random integer between 1 and 6
var randomdice = 1 + Math.floor(Math.random()*6);
document.getElementById("mydice").src= dice[randomdice].src;
}

function throwcoin(){
//create a random integer between 0 and 1
return Math.floor(Math.random()*2) == 0 ? "heads" : "tails";
}
</script>
<title>MEMO MATH TEST</title>
</head>
<body>
<img src="d1.gif" id="mydice">
<form>
<input type="button" value="Throw dice!" onClick="throwdice()">
<p>
<input type="button" value="TIRA MONEDA!" onClick="sayHello()">
<div id="result"></div>
</form>
</body>
</html>