Check if num==num2

**TimFA** · 11-21-2007, 09:59 PM

Code:

var ranNum= Math.floor(Math.random()*5);
function getNum()
{
var guessNum= getElementsByName("number");
}
function checkNum()
{
if (ranNum==guessNum)
{
alert("You win!")
}
else
{
alert("You lose!")
}
}

Will this check if inside a form the box named "number" equals the random number? I can't seem to get it working.

**Trinithis** · 11-21-2007, 10:45 PM

Code:

ranNum==guessNum.value

**codeexploiter** · 11-22-2007, 03:34 AM

Code:

var ranNum= Math.floor(Math.random()*5);
var guessNum;
function getNum(){
	guessNum= getElementsByName("number");
}

function checkNum(){
	if(ranNum == guessNum[0].value){
		alert("You win!")
	}else{
		alert("You lose!")
	}
}

I've made in guessNum variable global as in your code its scope limited to getNum function only.

The getElementsByName() method returns a collection of objects with the specified NAME (Array of objects). Even if it returns only one object it return it as array so you need to access the object using an index.

**Twey** · 11-22-2007, 03:45 AM

With some proper formatting your errors become clearer:

Code:

var ranNum= Math.floor(Math.random()*5);

function getNum() {
  // getElementsByName() is a method of document,
  // and needs to be accessed as such.
  // Also, it returns a collection of elements.

  // Using an ID and getElementById() would probably
  // be more appropriate.
  var guessNum= getElementsByName("number");
}

function checkNum() {
  // guessNum was defined locally to getNum(),
  // and so isn't available here.
  if (ranNum==guessNum) {
    alert("You win!")
  } else {
    alert("You lose!")
  }
}

How I'd do it:

Code:

var NumberGuess = {
  randNum: (function() {
    var a = function() {
      var n = Math.floor(Math.random() * 5);
      a.toString = function() { return n; };
      return a;
    };
    return a();
  })(),
  checkNum: function() {
    alert(document.getElementById("number").value
        == NumberGuess.randNum
      ? "You win"
      : "You lose");
  }
}

**TimFA** · 11-22-2007, 02:59 PM

How will it check?? I can't get it to submit the form to it, just displays the JavaScript (as expected), and if you just submit it, nothing happens. I read to code, and don't see any functions that need to be activated.

**Twey** · 11-22-2007, 03:06 PM

Code:

<form action="" onsubmit="NumberGuess.checkNum(); return false;">
  <div>
    <label>Guess:
      <input type="text" id="number">
    </label>
    <input type="submit" value="Check">
  </div>
</form>

**TimFA** · 11-22-2007, 03:16 PM

Still doesn't work.

Code:

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
  <meta content="text/html; charset=ISO-8859-1" http-equiv="content-type">
  <title></title>
  <script type="JavaScript">
var NumberGuess = {
  randNum: (function() {
    var a = function() {
      var n = Math.floor(Math.random() * 5);
      a.toString = function() { return n; };
      return a;
    };
    return a();
  })(),
  checkNum: function() {
    alert(document.getElementById("number").value
        == NumberGuess.randNum
      ? "You win"
      : "You lose");
  }
}
  </script>
</head>
<body>
<form action="" onsubmit="NumberGuess.checkNum(); return false;">
  <div>
    <label>Guess:
      <input type="text" id="number">
    </label>
    <input type="submit" value="Check">
  </div>
</form>
</body>
</html>

**jscheuer1** · 11-22-2007, 04:00 PM

Usually something like this won't hurt:

Code:

  <script type="JavaScript">

But, in this case it does. It should be:

Code:

<script type="text/javascript">

Edit: The type attribute is required, but many browsers will let you get away without it and/or accept the decremented language attribute. However, if you do use either, it should be used correctly. Best practice is to use the type attribute only, and to write it exactly as I have shown.