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Usage of the backtick character (`) in JavaScript

This is a feature called template literals. They were called “template strings” in prior editions of the ECMAScript 2015 specification. Template literals are supported by Firefox 34, Chrome 41, and Edge 12 and above, but not by Internet Explorer. Examples: http://tc39wiki.calculist.org/es6/template-strings/ Official specification: ECMAScript 2015 Language Specification, 12.2.9 Template Literal Lexical Components (a bit dry) Template literals can be used … Read more

How do I loop through or enumerate a JavaScript object?

You can use the for-in loop as shown by others. However, you also have to make sure that the key you get is an actual property of an object, and doesn’t come from the prototype. Here is the snippet: For-of with Object.keys() alternative: Notice the use of for-of instead of for-in, if not used it will return undefined on named … Read more

String.prototype.replaceAll() not working

There is no replaceAll in JavaScript: the error console was probably reporting an error. Instead, use the /g (“match globally”) modifier with a regular expression argument to replace:

My javascript is returning this error: $.ajax is not a function

You are using slim version of jQuery. It Doesn’t support ajax Calling. Use instead of it. Slim build Sometimes you don’t need ajax, or you prefer to use one of the many standalone libraries that focus on ajax requests. And often it is simpler to use a combination of CSS and class manipulation for all … Read more

Infinite Scrolling in Asp.Net MVC with jQuery / AJAX Issues

This is what I ended up doing based on the suggestion : Seems to work OK now thanks for that.

How to validate an email address in JavaScript

Using regular expressions is probably the best way. You can see a bunch of tests here (taken from chromium) Here’s the example of regular expresion that accepts unicode: But keep in mind that one should not rely only upon JavaScript validation. JavaScript can easily be disabled. This should be validated on the server side as well. Here’s an example of … Read more

How to check if array is empty or does not exist?

You want to do the check for undefined first. If you do it the other way round, it will generate an error if the array is undefined. Update This answer is getting a fair amount of attention, so I’d like to point out that my original answer, more than anything else, addressed the wrong order of the … Read more

HTTP Status 405 – Request method ‘POST’ not supported (Spring MVC)

I found the problem that was causing the HTTP error. In the setFalse() function that is triggered by the Save button my code was trying to submit the form that contained the button. when I remove the document.submitForm.submit(); it works: @Roger Lindsjö Thank you for spotting my error where I wasn’t passing on the right parameter!

Add days to JavaScript Date

You can create one with:- This takes care of automatically incrementing the month if necessary. For example: 8/31 + 1 day will become 9/1. The problem with using setDate directly is that it’s a mutator and that sort of thing is best avoided. ECMA saw fit to treat Date as a mutable class rather than an immutable structure.

What is the most efficient way to deep clone an object in JavaScript?

Native deep cloning It’s called “structured cloning”, works experimentally in Node 11 and later, and hopefully will land in browsers. See this answer for more details. Fast cloning with data loss – JSON.parse/stringify If you do not use Dates, functions, undefined, Infinity, RegExps, Maps, Sets, Blobs, FileLists, ImageDatas, sparse Arrays, Typed Arrays or other complex types within your object, a … Read more

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