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Found 6685 Articles for Javascript
![Amit Sharma](https://www.tutorialspoint.com/assets/profiles/14294/profile/60_103411-1513053466.png)
10K+ Views
Both onclick & href have different behaviors when calling JavaScript directly. Also the script in href won’t get executed if the time difference is short. This is for the time between two clicks.ExampleHere’s an example showing the usage of href vs onClick in JavaScript. Live Demo JavaScript href vs onClick() function myFunc() { var v = 0; for (var j=0; j
![Swarali Sree](https://www.tutorialspoint.com/assets/profiles/13515/profile/60_84115-1512649510.jpg)
5K+ Views
The scope of a variable is the region of your program in which it is defined. JavaScript variables have only two scopes.Global Variables − A global variable has a global scope which means it can be defined anywhere in your JavaScript code.Local Variables − A local variable will be visible only within a function where it is defined. Function parameters are always local to that function.Within the body of a function, a local variable takes precedence over a global variable with the same name. If you declare a local variable or function parameter with the same name as a global ... Read More
![Rahul Sharma](https://www.tutorialspoint.com/assets/profiles/14297/profile/60_102977-1513054044.jpg)
884 Views
Like many other programming languages, JavaScript has variables. Variables can be thought of as named containers. You can place data into these containers and then refer to the data simply by naming the container.Before you use a variable in a JavaScript program, you must declare it. Variables are declared with the var keyword as follows. You can also declare multiple variables with the same var keyword as follows − Storing a value in a variable is called variable initialization. You can do variable initialization at the time of variable creation or at a later point in ... Read More
![Samual Sam](https://www.tutorialspoint.com/assets/profiles/13514/profile/60_83486-1512649303.jpg)
1K+ Views
document.onloadIt gets fired prior to loading of images and other external content. document.onload event is fired before the window.onload.window.onloadIt gets fired when the complete page loads, which includes images, scripts, css, etc.ExampleHere’a an example to understand onload.Live Demo JavaScript Animation Click button below to move the image to right
![Amit Sharma](https://www.tutorialspoint.com/assets/profiles/14294/profile/60_103411-1513053466.png)
238 Views
To place JavaScript in external file create an external JavaScript file with the extension .js. After creating, add it to the HTML file in the script tag. The src attribute is used to include that external JavaScript file.If you have more than one external JavaScript file, then add it to the same web page to increase the performance of the page.Let’s say the following new.js is our external JavaScript file −function display() { alert("Hello World!"); }Now add the external JavaScript file to the HTML web page −
![Sai Subramanyam](https://www.tutorialspoint.com/assets/profiles/13512/profile/60_68191-1512710774.jpg)
1K+ Views
To enhance performance, try to keep JavaScript external. The separate code makes it easier for web browsers to cache. However, use inline scripts only when you’re making single page websites. Still, it's better to use external code i.e. external JavaScript. To place JavaScript in external file create an external JavaScript file with the extension .js. After creating, add it to the HTML file in the script tag. The src attribute is used to include that external JavaScript file. If you have more than one external JavaScript file, then add it to the same web page to increase the performance of ... Read More
![Rahul Sharma](https://www.tutorialspoint.com/assets/profiles/14297/profile/60_102977-1513054044.jpg)
2K+ Views
Anonymous FunctionsAnonymous, as the name suggests, allows creating a function without any names identifier. It can be used as an argument to other functions. This is how JavaScript anonymous functions can be used −var myfunc = function() { alert(‘This is anonymous'); }Another example can be the following −setTimeout(function() { alert('Demo'); }, 3000);Inline FunctionsAn inline function is a javascript function, which is assigned to a variable created at runtime. You can difference Inline Functions easily with Anonymous since an inline function is assigned to a variable and can be easily reused.This is how JavaScript inline functions can be used −var ... Read More
![Amit Sharma](https://www.tutorialspoint.com/assets/profiles/14294/profile/60_103411-1513053466.png)
7K+ Views
Create external JavaScript file with the extension .js. After creating, add it to the HTML file in the script tag. The src attribute is used to include that external JavaScript file.If you have more than one external JavaScript file, then add it in the same web page to increase performance of the page.Let’s say the following new.js is our external JavaScript file −function display() { alert("Hello World!"); }Now add the external JavaScript file to the HTML web page −
![Ali](https://www.tutorialspoint.com/assets/profiles/14292/profile/60_101553-1513052445.jpg)
349 Views
You can place the tags, containing your JavaScript, anywhere within your web page, but it is normally recommended that you should keep it within the tag or tag.It’s good for performance to add JavaScript in element. Here’s an example to add under … − Here’s an example to add under … −
![Rahul Sharma](https://www.tutorialspoint.com/assets/profiles/14297/profile/60_102977-1513054044.jpg)
776 Views
With JavaScript, you can put JavaScript anywhere on the page, whether inside or tag. But, it is a good practice to add JavaScript in the footer i.e. just before closing the tag. This is because −It loads script faster.It will not block any DOM content to load.It loads the web page before loading JavaScriptImproves display speedPage loads faster