AutoCAD Forum. Turn on suggestions. Auto-suggest helps you quickly narrow down your search results by suggesting possible matches as you type. Showing results for. Search instead for. Did you mean:. This page has been translated for your convenience with an automatic translation service. This is not an official translation and may contain errors and inaccurate translations. Autodesk does not warrant, either expressly or implied, the accuracy, reliability or completeness of the information translated by the machine translation service and will not be liable for damages or losses caused by the trust placed in the translation service.
How can I change multiple mtexts font at once? Back to Topic Listing Previous Next. Copyright by Refsnes Data. All Rights Reserved. W3Schools is Powered by W3. Default undefined. You can even update the contents of a web page with information retrieved from a web server—without having to load a new web page.
In short, JavaScript lets you make your websites more engaging, effective, and useful. But because not all browsers support these nifty additions and because you can do a whole lot more with forms and JavaScript , you still need JavaScript to build the best, most user-friendly and interactive forms.
Figure New information appears in response to mouse movements and clicks. With JavaScript, you can create your own interactive effects. And, honestly, some programming is like that. Still, JavaScript is more complex than either HTML or CSS, and programming often is a foreign world to web designers; so one goal of this book is to help you think more like a programmer.
Many web designers are immediately struck by the strange symbols and words used in JavaScript. In many ways, learning a programming language is a lot like learning another language.
You need to learn new words, new punctuation, and understand how to put them together so you can communicate successfully. When learning to speak a new language, you quickly realize that placing an accent on the wrong syllable can make a word unintelligible. Likewise, a simple typo or even a missing punctuation mark can prevent a JavaScript program from working, or trigger an error in a web browser.
Also, you might find some of the concepts related to programming a bit hard to follow at first. JavaScript is called a scripting language. Most of the programs running on your computer are written using languages that are compiled. Compiling is the process of creating a file that will run on a computer by translating the code a programmer writes into instructions that a computer can understand.
Once a program is compiled, you can run it on your computer, and because a compiled program has been converted directly to instructions a computer understands, it will run faster than a program written with a scripting language.
Unfortunately, compiling a program is a time-consuming process: You have to write the program, compile it, and then test it. A scripting language, on the other hand, is only compiled when an interpreter another program that can convert the script into something a computer can understand reads it.
In the case of JavaScript, the interpreter is built into the web browser. So when your web browser reads a web page with a JavaScript program in it, the web browser translates the JavaScript into something the computer understands. As a result, a scripting language operates more slowly than a compiled language, because every time it runs, the program must be translated for the computer.
Granted, most JavaScript programs are much simpler than the programs you use to read email, retouch photographs, and build web pages. But even though JavaScript programs also called scripts are simpler and shorter, they share many of the same properties of more complicated programs. In a nutshell, any computer program is a series of steps that are completed in a designated order. Print that is, display the message on the web page.
While you may never want to print a welcome message on a web page, this example demonstrates the fundamental process of programming: Determine what you want to do, then break that task down into individual steps. Every time you want to create a JavaScript program, you must go through the process of determining the steps needed to achieve your goal.
But most browsers also have something called a JavaScript interpreter. In fact, web browsers let you leave out the type attribute in HTML 4. To add a script to your page, start by inserting these tags.
JavaScript was originally created as a client-side language. Client-side JavaScript is delivered to web browsers by a web server. The people visiting your site download your web page and its JavaScript, and then their web browser—the client—processes the JavaScript and makes the magic happen.
Server-side programming languages, as the name suggests, run on a web server. They can exhibit a lot of intelligence by accessing databases, processing credit cards, and sending email around the globe.
The problem with server-side languages is that they require the web browser to send requests to the web server, forcing visitors to wait until a new page arrives with new information. Client-side languages, on the other hand, can react immediately and change what a visitor sees in his web browser without the need to download a new page. Content can appear or disappear, move around the screen, or automatically update based on how a visitor interacts with the page.
This responsiveness lets you create websites that feel more like desktop programs than static web pages. You can also use plug-ins to add programming smarts to a web page. Java applets are one example. These are small programs, written in the Java programming language, that run in a web browser. They also tend to start up slowly and have been known to crash the browser.
Flash is another plug-in based technology that offers sophisticated animation, video, sound, and lots of interactive potential. Failed to load latest commit information. Aug 3, Sep 14, Replace Deflater with pako Dec 7, Jul 21, Nov 3, Fixes to types Oct 28, Sep 8, Add codeclimate configs. Oct 8, Resolve fonts using CSS Level 3 algorithm when using html Jan 14, May 4, Update lgtm.
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