I am having problems when I try to pull it up on my computer the page is blank. I am not understanding this. Like when you click on the file button on the internet and you click open file that file shows up blank. Can someone help me understand why it is doing that. Thanks.
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="content-type" content="text/html;charset=UTF-8" />
<title>Week 10</title>
<script type="text/javascript">
/ *<![CDATA[ */
Var name;
firstName = "Valerie";
lastName ="Shipbaugh";
var placeOfBirth;
name=FirstName +"";
name += lastName;
placeOfBirth ="Houston";
placeOfBirth +=",Texas";
nameArray = name.split("");
/*]]>*/
</script>
</head>
<body>
<script type="text/javascript">
//<![CDATA[
document.write("<p> My first name is : + nameArray[0]
+ "<br />");
document.write("My last name is: "+ nameArray[1]
+ "<br />");
*/
The brackets[] specifies alternate characters allowed in a patch pattern.
It uses metacharacters which are special characters that define the pattern matching rules ina regular experession.
*/
document.write("There are " + firstName.length
+ " characters in my first name" + " <br/>");
*/
This one called the length property.
This returns the number of characters in a string.
*/
document.write("I was born in " + placeOfBirth + " <br/>");
*/
With this string we are using concatenation operations.
*/
document.write("<p>My initials are: " + firstName.charAt(0) +
lastName.charAt(0) + "</p>");
*/
The last one return the character at the specific position in a text string
returns an empty string if the specified position is greater than the length of the string.
*/
//]]>
</script>
</body>
</html>
So where my comments are to explain what is going on is in the wrong place???
There is a more general way to solve this problem:
Take everything out of this file and
copy it into notepad.
Put just the
<html>and </html> into the file
Begin copying very small blocks into
the file one at a time, each time
reload the page
Soon you will see
one small block that causes the
failure, then you can assess that
small block.
Look at errors reported by the browser (tools->error console in firefox for example) it will hi-light errors such as you mismatched /**/ comments & the missing closing quote character from;
document.write("<p> My first name is : + nameArray[0]
Also js is case sensitive so its var not Var, which you should use to define all your variables such as firstname (which you incidentally later refer to as Firstname) etc.
Of course it won't work, the comment blocks aren't even right:
*/
The brackets[] specifies alternate characters allowed in a patch pattern.
It uses metacharacters which are special characters that define the pattern
matching rules ina regular experession.
*/
Should be:
/*
The brackets[] specifies alternate characters allowed in a patch pattern.
It uses metacharacters which are special characters that define the pattern
matching rules ina regular experession.
*/
Also, you really should avoid using document.write. In certain cases, that is what causes a blank page (if I remember correctly, when you use it after page load).
JavaScript is case sensitive - so in the first section of your scripts:
Var name; //var is with a lowecase "v"
firstName = "Valerie";
lastName ="Shipbaugh";
var placeOfBirth;
name=FirstName +""; //firstName was created with a lowecase "f"
Later you have this...
document.write("<p> My first name is : + nameArray[0]
+ "<br />");
You're missing a quote in there, should be
document.write(" My first name is : " + nameArray[0]
+ "");
And finally, comments open and close like this:
/* comment */
Not like this
*/ error */
Fixing these things will make the script run. However, it's not doing what I suspect you want. You are trying to split() the string containing the name, but there's nothing to split it on. You need to add a space between then and try this:
nameArray = name.split(" ");
You can see this working here:
http://jsfiddle.net/CM7fx/
Test in multiple browsers and make sure you have javascript enabled id' suggest first
The comments were wrong, the variable name are case sensitive. Here is a working version without comments, you can re-add those
<head>
<meta http-equiv="content-type" content="text/html;charset=UTF-8" />
<title>Week 10</title>
<script type="text/javascript">
var name;
var firstName = "Valerie";
var lastName ="Shipbaugh";
var placeOfBirth;
name= firstName + " " + lastName;
placeOfBirth ="Houston ,Texas";
var nameArray = name.split(" ");
</script>
</head>
<body>
<script type="text/javascript">
document.write("<p> My first name is : " + nameArray[0] + "<br />");
document.write("My last name is: " + nameArray[1] + "<br />");
document.write("There are " + firstName.length + " characters in my first name" + " <br/>");
document.write("I was born in " + placeOfBirth + " <br/>");
document.write("<p> My initials are: " + firstName.charAt(0) + lastName.charAt(0) + "</p>");
</script>
</body>
</html>
Related
help me out guys, i dont seem to know why the error is popping up. (i started learning javacript and i'm testing out how a string operator looks like)
<html>
<head><title>Head</title></head>
<body></body>
<script>
var age=27;
var info = "my name is Daniel, i am " +age + " years old " + 10;
console.log(info);
</script>
</html>
Uncaught SyntaxError: expected expression, got '<' debugger eval code:1
add script inside this BODY tag, and You can code like this
<html>
<head><title>Head</title></head>
<body>
<script>
var age=27;
// var info = "my name is Daniel, i am " +age + " years old " + 10;
var info = `my name is Daniel, i am ${age} years old 10`;
console.log(info);
</script>
</body>
</html>
The error is a JS error, not an HTML. If you put everything in JS(including HTML too) you probably get this error.
Either create two seperate files(.JS and .HTML) and put reference of .js in HTML
Put everything in HTML.
1. Two Files(JS and HTML)
var age = 27;
var info = "my name is Daniel, i am " + age + " years old " + 10;
console.log(info);
<html>
<head>
<title>Head</title>
</head>
<body></body>
</html>
2. Single HTML file
<html>
<head>
<title>Head</title>
</head>
<body></body>
<script>
var age = 27;
var info = "my name is Daniel, i am " + age + " years old " + 10;
console.log(info);
</script>
</html>
and I need help understanding some parts of this
Example I am doing out the Sams Teach Yourself HTML, CSS, and JavaScript.
A few things they did not explain in the lesson is this line here
"i = Math.floor(Math.random() * quotes.length);"
How does quotes.length and Math.random work?
Also I am having a hard time understanding this block of code..
"//Write out the quote as HTML
document.write("<p style='background-color: #ffb6c1'>\"");
document.write(quotes[i] + "\"");
document.write("<em>-" + sources[i] + "</em>");
document.write("</p>");"
Any help will be appreciated.
<!DOCTYPE html>
<html>
<head lang="en">
<meta charset="UTF-8">
<title>Quotable Quotes</title>
<script>
<!-- Hide the script from old browsers
function getQuote() {
//Create the Arrays
var quotes = new Array(4);
var sources = new Array(4);
// Initialize the arrays with quotes
quotes[0] = "When I was a boy of 14, my father was so " +
"ignorant...but when I got to be 21 I was astonished" +
"at how much he had learned in 7 years.";
sources[0] = "Mark Twain";
quotes[1] = "Everybody is ignorant. Only on different " +
"subjects.";
sources [1] = "Will Rogers";
quotes[2] = "They say such nice things about people at " +
"their funerals that it makes me sad that I'm going to " +
"miss mine by just a few days.";
sources[2] = "Garrison Keillor";
quotes[3] = "What's another word for thesaurus?";
sources[3] = "Steven Wright";
//Get a random index into the arrays
i = Math.floor(Math.random() * quotes.length);
//Write out the quote as HTML
document.write("<p style='background-color: #ffb6c1'>\"");
document.write(quotes[i] + "\"");
document.write("<em>-" + sources[i] + "</em>");
document.write("</p>");
}
// Stop hiding the script -->
</script>
<meta name="viewport"
content="width=device-width, initial-scale=1">
</head>
<body>
<h1>Quotable Quotes</h1>
<p>Followinhg is a randon quotable quote. To see a new quote just reload this page</p>
<script>
<!-- Hide the script from old browsers
getQuote();
// Stop hiding the script -->
</script>
</body>
</html>
Math.random() produces a random number between 0 and 1. And quotes.length wll return the number of items in the quotes array, which in your case is 4.
In the code, you are trying to get a random quote from the quotes array. And you must be knowing by now that to access an element from an array we have to use index.
So by this line, we are generating a valid random index that could help us get a quote out from the quotes array.
If you think, maximum length of quotes array could be 4 multiplied by (take the biggest random number Math.random() could generate) 0.9 which would be less than 4 and a float, so Math.floor takes care of that and rounds the number downwards to the nearest integer making it equal to 3 which is the last quote. And in this way you get random quotes.
i = Math.floor(Math.random() * quotes.length);
Now onto this:
It's just writing html to the DOM (Document Object Model). DOM defines the logical structure of the documents and the way in which they are accessed and manipulated.
So basically you are just writing the html encapsulated in the quotes to the document.
document.write("<p style='background-color: #ffb6c1'>\");
document.write(quotes[i] + "\"");
document.write("<em>-" + sources[i] + "</em>");
document.write("</p>");"
I have written some code that works fine but I am trying to make a space between the strings.
The code I have is:
<html>
<head>
<title> Concatenating Strings </title>
</head>
<body>
<script type = "text/javascript">
var greetingString = "Hello";
var myName = prompt ("Please enter your name","");
var concatString;
document.write(greetingString + "" + myName + "<br>");
concatString = greetingString + "" + myName;
document.write(concatString);
</script>
</body>
</html>
At the moment the script shows HelloMichael, I am wanting it to show Hello Michael. Can someone please advise me on how I can do that?
To insert a space character, simply insert a space character. For example:
greetingString + " " + myName
There's no space in your current output, because "" doesn't have a space in it.
put a space between hello and michael like this:
concatString = greetingString + " " + myName; //notice the space in the string
concatString = greetingString + " " + myName;
Simply change your "" to " ", the second has a space in it.
I am trying to create code that when you press a button, it will change the value of a variable and replace some text.
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
</head>
<body>
<p id="unitts">You have 0 unitts</p>
<script type="text/javascript">
var unitt = 0;
function unittIncrease() {
var unittPrev = unitt;
unitt++;
document.getElementById(unitts).innerHTML.replace("You have " + unittPrev.toString() + " unitts.", "You have " + unitt.toString() + " unitts.");
}
</script>
<button id="unittIncrease" onclick="unittIncrease();">Digitize Unitt</button>
</body>
</html>
When I press the button, nothing happens to the text.
I don't know why this does not work.
Please help me!
EDIT: I am only 11 years old,
please don't throw your wizard
code at me.
maybe you should remove your button system and add a while loop that
automatically add a unit but waits one second with a setInterval
function
I think you should write the js code like this
document.getElementById('unitts').innerHTML = "You have"....
Instead of:
document.getElementById(unitts).innerHTML.replace("...")
Your JavaScript should be (note the unitts wrapped in quotes and the full stop removed):
document.getElementById('unitts').innerHTML = "You have " + unitt + " unitts";
Instead of:
document.getElementById(unitts).innerHTML.replace("You have " + unittPrev.toString() + " unitts.", "You have " + unitt.toString() + " unitts.");
In the latter, it is looking for the non-existent variable unitts instead of the string 'unitts'. Also, you are looking for the text You have x unitts. which cannot be found because in your HTML, it is just You have x unitts without the full stop.
Edit
See this plnkr.
Apart from the issues that the other answer mentions, by calling .replace method on the .innerHTML property of the element, the content of it doesn't change. You should reset the property by using the returned value of the method call:
el.innerHTML = el.innerHTML.replace(...);
Also, as you are trying to increase a number, instead of replacing all the characters, you can just replace the numeric part:
var unitts = document.getElementById('unitts');
function unittIncrease() {
unitts.textContent = unitts.textContent.replace(/\d+/, function(n) {
return +n + 1;
});
}
https://jsfiddle.net/h6odbosg/
I am still fairly new to Javascript and I am having some trouble getting a function to run properly. Here is what I have:
<script type='text/javascript'>
function GravityCalc (ratio, name)
{
Weight = getElementById('WeightBox').value * ratio;
document.getElementById('WeightText').innerHTML = 'You would weigh ' + weight + ' on ' + name;
}
</script>
Enter Weight: <input type='text' id='WeightBox' name='Weight'><br>
<button onclick='GravityCalc(2.3,Jupiter)'>calculate</button>
<div id='WeightText'> </div>
The form displays perfectly, but nothing happens when the button is pressed. It also should probably be noted that eventually, the name and ratio parameters is going to be parsed in with PHP.
You have a couple things wrong...
'Weight' should be 'weight'. JS is case sensitive, and you had it in Camel case in one line and Pascal case in another line.
You need to use 'document.getElementById'. Just 'getElementById' doesn't work in all browsers.
You need to declare the 'Weight' variable.
The value in a dom element is stored as a string or char array if you will, thus you need to parse it to an int, like so, parseInt(document.getElementById('WeightBox').value)
Here's my JSFiddle... http://jsfiddle.net/EH5j6/
function GravityCalc (ratio, name)
{
var weight;
weight = parseInt(document.getElementById('WeightBox').value) * ratio;
document.getElementById('WeightText').innerHTML = 'You would weigh ' + weight + ' on ' + name;
}
javascript variables are case sensitive! Your Ws didn't match up. I also highly recommend using var to explicitly declare your variables.
var weight = getElementById('WeightBox').value * ratio;
document.getElementById('WeightText').innerHTML = 'You would weigh ' + weight + ' on ' + name;
plus, as a commenter noted, strings must be enclosed by quotes.
<button onclick='GravityCalc(2.3,"Jupiter")'>calculate</button>
Make sure that you include the javascript in the head of the html page.
function calc (ratio, name) {
var weight = document.getElementById('WeightBox').value * ratio;
document.getElementById('WeightText').innerHTML = "You would weigh " + weight + " on " + name;
}
and change the HTML to be:
Enter Weight: <input type='text' id='WeightBox' name='Weight'><br>
<button onclick="calc(2.3, 'Jupiter')">calculate</button>
<div id='WeightText'> </div>