How to reverse a string in javascript w3schools
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Copyright 1999-2022 by Refsnes Data. All Rights Reserved. String methods help you to work with strings. String Methods and PropertiesPrimitive values, like "John Doe", cannot have properties or methods (because they are not objects). But with JavaScript, methods and properties are also available to primitive values, because JavaScript treats primitive values as objects when executing methods and properties. JavaScript String LengthThe Example let txt = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"; Try it Yourself » Extracting String PartsThere are 3 methods for extracting a part of a string:
JavaScript String slice()
The method takes 2 parameters: the start position, and the end position (end not included). ExampleSlice out a portion of a string from position 7 to position 13 (13 not included): let str = "Apple, Banana, Kiwi"; Try it Yourself » NoteJavaScript counts positions from zero. First position is 0. Second position is 1. If a parameter is negative, the position is counted from the end of the string. This example slices out a portion of a string from position -12 to position -6: Example let str = "Apple, Banana, Kiwi"; Try it Yourself » If you omit the second parameter, the method will slice out the rest of the string: or, counting from the end: JavaScript String substring()
The difference is that start and end values less than 0 are treated as 0 in Example let str = "Apple, Banana, Kiwi"; Try it Yourself » If you omit the
second parameter, JavaScript String substr()
The difference is that the second parameter specifies the length of the extracted part. Example let str = "Apple, Banana, Kiwi"; Try it Yourself » If you omit the second
parameter, If the first parameter is negative, the position counts from the end of the string. Example let str = "Apple, Banana, Kiwi"; Try it Yourself » Replacing String ContentThe Example let text = "Please visit Microsoft!"; Try it Yourself » NoteThe The The If you want to replace all matches, use a regular expression with the /g flag set. See examples below. By default, the Example let text = "Please visit Microsoft and Microsoft!"; Try it Yourself » By default, the Example let text = "Please visit Microsoft!"; Try it Yourself » To replace case insensitive, use a regular expression with an Example let text = "Please visit
Microsoft!"; Try it Yourself » NoteRegular expressions are written without quotes. To replace all matches, use a regular expression with a Example let text = "Please visit Microsoft and Microsoft!"; Try it Yourself » Converting to Upper and Lower CaseA string is converted to upper case with A string is converted to lower case with JavaScript String toUpperCase()Example let text1 = "Hello World!"; Try it Yourself » JavaScript String toLowerCase()Example let text1 = "Hello World!"; // String Try it Yourself » JavaScript String concat()
Example let text1 = "Hello"; Try it Yourself » The Example text = "Hello" + " " + "World!"; NoteAll string methods return a new string. They don't modify the original string. Formally said: Strings are immutable: Strings cannot be changed, only replaced. JavaScript String trim()The JavaScript String trimStart()ECMAScript 2019 added the String method The Example let text1 = " Hello World! "; Try it Yourself » JavaScript String
JavaScript String trimEnd()ECMAScript 2019 added the String method The JavaScript String
JavaScript String PaddingECMAScript 2017 added two String methods: JavaScript String padStart()The NoteThe To pad a number, convert the number to a string first. See the example below. Example let numb
= 5; Try it Yourself » Browser Support
It is supported in all modern browsers:
JavaScript String padEnd()The NoteThe To pad a number, convert the number to a string first. See the example below. Example let numb = 5; Try it Yourself » Browser Support
It is supported in all modern browsers:
Extracting String CharactersThere are 3 methods for extracting string characters:
JavaScript String charAt()The JavaScript String charCodeAt()The The method returns a UTF-16 code (an integer between 0 and 65535). Property AccessECMAScript 5 (2009) allows property access [ ] on strings: NoteProperty access might be a little unpredictable:
Example let text = "HELLO WORLD"; Try it Yourself » Converting a String to an ArrayIf you want to work with a string as an array, you can convert it to an array. JavaScript String split()A string can be converted to an array with
the Example text.split(",") // Split on commas Try it Yourself » If the separator is omitted, the returned array will contain the whole string in index [0]. If the separator is "", the returned array will be an array of single characters: Complete String ReferenceFor a complete String reference, go to our: Complete JavaScript String Reference. The reference contains descriptions and examples of all string properties and methods. Test Yourself With ExercisesExercise:Convert the text into an UPPERCASE text: let txt = "Hello World!"; txt = txt.; Start the Exercise How do you reverse a string in JavaScript?Use reverse() function in JavaScript to reversal the array of characters i.e. [ 's', 'k', 'e', 'e', 'G', ' ', 'r', 'o', 'f', ' ', 's', 'k', 'e', 'e', 'G' ] Use join() function in JavaScript to join the elements of an array into a string.
How do you reverse something in JavaScript?Using Built-in Methods to Reverse the String - split(), reverse() and join() The simplest way to reverse a string in JavaScript is to split a string into an array, reverse() it and join() it back into a string. With ES6, this can be shortened and simplified down to: let string = "!
How can we reverse a string?The reversing of a string is nothing but simply substituting the last element of a string to the 1st position of the string. Different Methods to Reverse a String in C++ are: Making our own reverse function. Using 'inbuilt' reverse function.
Does JavaScript have a reverse function?The reverse() method reverses an array in place and returns the reference to the same array, the first array element now becoming the last, and the last array element becoming the first. In other words, elements order in the array will be turned towards the direction opposite to that previously stated.
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