Function trim() remove spaces at the beginning and end of a line JavaScript

Компьютер, программы

→

JavaScript - programming language for HTML

→

Text, strings in the JavaScript

Function trim() remove spaces at the beginning and end of a line JavaScript | standard ES5

посмотрели 25460 раз

обновлено: 1 Augusta 2020

Function trim returns a string, removing spaces at the beginning and end of the line. The function does not change the current row.

Syntax

Params

Return value

stringObj.trim()

returns a string with spaces removed at the beginning and end of the line

Example

Html

← Previous topic
Function startsWith(text) Checks, whether the line begins with the specified substring JavaScript | standard ES5

Next topic →
The padStart(length, symbol) function appends characters at the beginning of a line up to the desired JavaScript line length | ES5 standard

Your feedback ... 4 Comments

gfhaa
7 May 2021 22:22

сколько лет этому сайту?

answer

guest (14 Augusta 2021 21:31) много answer

guest (28 Augusta 2021 13:55) 0 answer

guest (8 March 2022 23:09) Думаю тебя еще не было. answer

guest
9 September 2021 12:20

1 1 1 1

answer

guest
31 October 2021 11:19

Охуенный сайт!!!

answer

guest
6 July 2022 17:18

Зачет!!!

answer

Объявления

• In which editor (program) is it convenient to write JavaScript code?

[bgcolor=#D0F2A0]New app[/bgcolor]

• Create a new application JavaScript in a text editor

• Create a new application JavaScript in Visual Studio Code. Debug the application. See in debugging how to perform JavaScript

[bgcolor=#D0F2A0]Debugging JavaScript, HTML[/bgcolor]

• Debug JavaScript in Google Chrome. Using debugger

• How to find out (see) where the error is when executing HTML, JavaScript in Google Chrome

• Debugging JavaScript in the Google Chrome. Use console.log("Hello!")

JavaScript standard ES5. It was published in 2009. Supported by all browsers

[bgcolor=#D0F2A0]Function

• Function in the JavaScript. Example: function CalculateSum(value1, value2) { ... } | standard ES5

• Function return || in the JavaScript. Example: function getPersonName(name) { return name || "Evgen" } | standard ES5

• Call a function before it is defined (Hoisting) in the JavaScript | standard ES5

• Variables within a function (lifetime of variables within a function) JavaScript | standard ES5

• Pass parameters by value and by reference to the function in the JavaScript | standard ES5

• How to find out... whether there is a function by name in the JavaScript? Example: typeof calcSum == "function" | standard ES5

• The function described inside the function. JavaScript | standard ES5

[bgcolor=#D0F2A0]Unnamed function[/bgcolor]

• Unnamed function in the JavaScript . Using an unnamed function: create a new variable and assign an unnamed function to a new variable. Example: var myFunc1 = function (a, b) { return a + b; } ; | standard ES5

• Unnamed function in the JavaScript . Using an unnamed function: pass an unnamed function as a parameter to another function. Example: Calculate(15, 7, function(v1, v2) {return v1+v2;}); | standard ES5

[bgcolor=#D0F2A0]Self-calling unnamed function[/bgcolor]

• Self-calling unnamed function in the JavaScript. Where is it used? Used in Yandex advertising. Example: ( function(){ ... } )(); | standard ES5

• Create a file js with an object containing export variables and functions. This is an example of using a self-calling unnamed function | standard ES5

[bgcolor=#D0F2A0]Lambda function (abbreviated version of the unnamed function)[/bgcolor]

• Lambda function in the JavaScript . Use the lambda function. [Example1] var myFunc1 = (a, b) => a + b; [Example2] Calculate(15, 7, (v1, v2) => {return v1+v2;}); | standard ES5

[bgcolor=#D0F2A0]Variables[/bgcolor]

• Variables in the JavaScript (text, number, flag, date and time) | standard ES5

• Accessing Variables Before Defining Them (Hoisting) in the JavaScript | standard ES5

• Variable scope var, let, const in the JavaScript | standard ES5

Text, strings in the JavaScript

• Text in the JavaScript. Class String. Example: var myText = String("World"); | standard ES5

• Length (string length in the JavaScript) | standard ES5

• Function replace(text1, text2) replace text in the JavaScript | standard ES5

• Function toUpperCase() converts text to uppercase JavaScript | standard ES5

• Function toLowerCase() lowercase text JavaScript | standard ES5

• Function split(delimiter) splits a string into substrings JavaScript | standard ES5

• Function charAt(position) get a symbol by position JavaScript | standard ES5

• Function substr(pos, len) returns a substring JavaScript | standard ES5

• Function slice(pos1, pos2) returns a substring JavaScript | standard ES5

• Function substring(pos1, pos2) returns a substring JavaScript | standard ES5

• Function indexOf(text, startPos) searches for a substring and returns an index JavaScript | standard ES5

• Function startsWith(text) Checks, whether the line begins with the specified substring JavaScript | standard ES5

• Function trim() remove spaces at the beginning and end of a line JavaScript | standard ES5

• The padStart(length, symbol) function appends characters at the beginning of a line up to the desired JavaScript line length | ES5 standard

• The padEnd(length, symbol) function appends characters at the end of a line up to the desired JavaScript line length | ES5 standard

• You can assign text as many lines to a text variable. Example: var myText = `Hello \n Thanks \n Bye` | JavaScript ES6 standard

• In a text variable, you can write expressions with variables (formatting, string interpolation). Example: var myText = `Hello ${a}` | JavaScript standard ES6

[bgcolor=#D0F2A0]Regular expressions[/bgcolor]

• Regular expressions in JavaScript | ES5 standard

• Write a regular expression to remove all special characters except letters and numbers | Regex JavaScript | standard ES5

[bgcolor=#D0F2A0]Numbers and mathematical functions[/bgcolor]

• Number in the JavaScript. Convert text to a number. Rounding a number. Convert hexadecimal to decimal. | standard ES5

• Mathematical functions from the library Math: Sin, cos, log, pow and so on in the JavaScript | standard ES5

[bgcolor=#D0F2A0]Date & Time[/bgcolor]

• Date & Time (year, month, date, hours, minutes, seconds) in the JavaScript. Class Date | standard ES5

[bgcolor=#D0F2A0]Array[/bgcolor]

• Array in the JavaScript This is [] or class Array | standard ES5

• What does 3 dots mean... items | Example 1: Math.max(... prices) | Example 2: books.push(... items) | JavaScript, ES5 standard

• Difference between push(items) and push(...items) | Adding an Array to an Array in the JavaScript | standard ES5

• Find max prices in a complex array: [ {name:"Tomate", price:10}, {name:"Apple", price:17}, {name:"Orange", price:15} ] in JavaScript | ES5 standard

• Find min prices in a complex array: [ {name:"Tomate", price:10}, {name:"Apple", price:17}, {name:"Orange", price:15} ] in JavaScript | ES5 standard

[bgcolor=#D0F2A0]Collection Map and Set[/bgcolor]

• Collection "The key-meaning" in the JavaScript. Class Map | standard ES5

• Collection of unique values in the JavaScript. Class Set | standard ES5

[bgcolor=#D0F2A0]Object {set of properties and functions}[/bgcolor]

• {} it"s an object in the JavaScript. An object contains a set of properties and functions. Example var book = {Name: "Wizard of the Mediterranean", Price: 120}; | standard ES5

• {...} = object in JavaScript is populated from class variables or another object. Example: const {name, total, price} = b.myProps; | ES5 standard

[bgcolor=#D0F2A0]Class (it is a function using new) | ES5 standard[/bgcolor]

• Class in the JavaScript this is a common constructor function. Such a constructor function contains simple data, objects, internal functions in the JavaScript. To create a class object, use new Example: function Book() { ... } ... var obj1 = new Book(); | ES5 standard

• Encapsulating variables (hiding variables for access) in the function (as a class) in the JavaScript | standard ES5

• prototype - is a set of functions, variables for all instances of the class (as a function) in the JavaScript | standard ES5

[bgcolor=#D0F2A0]try catch[/bgcolor]

• Why you need to use try and catch in the JavaScript? | standard ES5

[bgcolor=#D0F2A0]Closing (closure) in the Javascript[/bgcolor]

• What are closures? (closure) in the JavaScript ? Standard ES5

[bgcolor=#D0F2A0]Memory management in JavaScript[/bgcolor]

• Memory management in JavaScript | ES5 standard

[bgcolor=#D0F2A0]Examples of picture movement and animation[/bgcolor]

• Animation of the little man on the spot. Use the HTML element <div>. For animation, we use CSS styles: "animation", "background-image", "background-position", "keyframes" | ES5 standard

• Animation of a man in motion (sprite). Use HTML elements <div>, <img>. For animation, we use CSS styles: "animation", "background-image", "background-position", "keyframes" | ES5 standard

• Draw a picture with movement. Use the HTML element<canvas>. Use JavaScript for movement: var img = new Image(), img.src = url, drawImage, timer, window.setInterval | standard ES5

• Drawing a picture with movement and animation (sprite). Use the HTML element <canvas>. Use JavaScript for movement: var img = new Image(), img.src = url, drawImage, timer, window.setInterval | standard ES5

[bgcolor=#D0F2A0]Examples[/bgcolor]

• How to identify a device (tablet, computer, phone) that is currently used in JavaScript, HTML | ES5 standard

• Text Editor write in HTML, JavaScript | standard ES5

Do Popup using HTML and Javascript

• How to make a Popup window in a HTML page | Javascript, HTML, CSS

My Game (HTML, JavaScript)

• My game "Wizard World" | HTML, JavaScript

PDF readers. Upload and display a PDF file (JavaScript, HTML)

• PDF reader. Download and display a PDF file (adobe JavaScript, HTML) | PDF JavaScript implemented by Adobe

• PDF reader. Download and display a file PDF (JavaScript, HTML) | PDF JavaScript implemented by Mozilla

JavaScript standard ES6. It was published in 2015. Not supported by all browsers. Synonyms ES6, ES2015, ECMAScript 2015

• In a text variable, you can write expressions with variables (formatting, string interpolation). Example: var myText = `Hello ${a}` | JavaScript standard ES6

• class | Class in the JavaScript. Example: class Book {...} ... var obj1 = new Book(); | ES6 standard

• promise in the JavaScript | standard ES6