Clear string in javascript

How to remove text from string in JavaScript ?

JavaScript is widely used language. We may sometime need to remove text from string to get a desired output from certain API calls or even within an JavaScript APP. Answers to your question on how to remove text from string in JavaScript are mentioned below.

Removing Text using String.prototype.replace()

Using this method does not alter the original string but returns a new string.
For instance:

var str = "Hello World!"; var newStr = str.replace('Hello', 'Hy'); console.log(newStr); // Prints: Hy World!

In order to remove all occurrences of the word “Hello” we can write following line.

Removing Text in JavaScript using slice() method

The slice() method extracts parts of a string and returns the extracted parts as a new string. It takes two parameter which specify the parts of the string to be extracted.

Syntax: string.slice(start, end)

start: Specifies the position to begin the extraction. This parameter is mandatory. The first character is at position 0.

end: Specifies the position where the extraction should end. This parameter is optional and if not provided, slice() selects all characters from the start-position to the end of the string.

Here’s an example on how to remove text from string in JavaScript using slice() method:

var str = "Hello World!"; var result = str.slice(0); console.log(result); // Prints: Hello World! as the starting position is 0.

var str = "Hello World!" var result = str.slice(2); console.log(result); //Prints: llo World!

Providing both the parameters and extracting the string

var str = "Hello World!"; var result = str.slice(2, 8); console.log(result); //Prints: llo Wo

We can give negative value to start parameter in order to start from the end of the string.

var str = "Hello World!"; var result = str.slice(-1); console.log(result); //Prints: !

Custom method to delete word from string in JavaScript

String.prototype.removeWord = function(searchWord) < var str = this; var n = str.search(searchWord); while(str.search(searchWord) >-1) < n = str.search(searchWord); str = str.substring(0, n) + str.substring(n + searchTerm.length, str.length); >return str; > //Using above method var string = "Today is is Monday"; string.removeWord('is'); // Returns: Today is Monday

JavaScript code to remove text from string and extract only Number

For this we’ll be using Regular Expression and match that to the given string and get the output as number. Here’s an example code snippet on how to remove text from string in JavaScript and extract number from the string.

Number(("data-123").match(/\d+$/)); // strNum = 123

Here’s what the statement above does…working middle-out:

1. str.match(/\d+$/) – returns an array containing matches to any length of numbers at the end of str. In this case it returns an array containing a single string item [‘123’].
2. Number() – converts it to a number type. Because the array returned from .match() contains a single element Number() will return the number.

How to remove text inside brackets using Regular Expressions in JavaScript

Let’s jump straight into the code to learn how to remove text inside brackets using Regular Expressions in JavaScript.

"Hello, this is Mike (example)".replace(/ *\([^)]*\) */g, ""); //Result "Hello, this is Mike"

Here, we are using regular expression / *\([^)]*\) */g that finds the characters inside brackets (in this case small round brackets) and replace them with empty string.

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JavaScript clear method

We can clear string from a selected string or text by the use of selection object’s clear() method.

JavaScript clear method

JavaScript clear method

We can clear string from a selected string or text by the use of selection object’s clear() method. It?s very simple to implement this clear method of JavaScript’s selection object.

In the script tag we have created the function deleteSelect() for clearing the selection. This deleteSelection() method is called when user calls this method by clicking on the button «Delete Selection». When user selects some text then this value goes automatically in the selection object and by calling the method clear() it deletes the selected value.

Here is the full html code for the clearExample.html as follows:

Delete Selection Example select any part of this string to delete its component Delete Selection

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8. What is JavaScript? — Definition
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How to Remove All Spaces from a String in JavaScript

To remove all spaces from a string in JavaScript, call the replaceAll() method on the string, passing a string containing a space as the first argument and an empty string ( » ) as the second. For example, str.replaceAll(‘ ‘, ») removes all the spaces from str .

const str = 'A B C'; const allSpacesRemoved = str.replaceAll(' ', ''); console.log(allSpacesRemoved); // ABC

The String replaceAll() method returns a new string with all matches of a pattern replaced by a replacement. The first argument is the pattern to match, and the second argument is the replacement. So, passing the empty string as the second argument replaces all the spaces with nothing, which removes them.

Note

Strings in JavaScript are immutable, and replaceAll() returns a new string without modifying the original.

const str = 'A B C'; const allSpacesRemoved = str.replaceAll(' ', ''); console.log(allSpacesRemoved); // ABC // Original not modified console.log(str); // A B C 

2. String replace() Method with Regex

Alternatively, we can remove all spaces from a string by calling the replace() method on the string, passing a regular expression matching any space as the first argument, and an empty string ( » ) as the second.

const str = 'A B C'; const allSpacesRemoved = str.replace(/ /g, ''); console.log(allSpacesRemoved); // ABC

We use the g regex flag to specify that all spaces in the string should be matched. Without this flag, only the first space will be matched and replaced:

const str = 'A B C'; // No 'g' flag in regex const spacesRemoved = str.replace(/ /, ''); // Only first space removed console.log(spacesRemoved); // AB C 

The String replace() method returns a new string with all the matches replaced with the second argument passed to it. We pass an empty string as the second argument to replace all the spaces with nothing, which removes them.

Note

As with replaceAll() , replace() returns a new string without modifying the original.

const str = 'A B C'; const spacesRemoved = str.replace(/ /g, ''); console.log(spacesRemoved); // ABC // Original not modified console.log(str); // A B C 

Tip

The regular expression we specified only matches spaces in the string. To match and remove all whitespace characters (spaces, tabs and newlines), we’ll have to use a different regex:

const str = 'A B C \t D \n E'; const whitespaceRemoved = str.replace(/\s/g, ''); console.log(whitespaceRemoved); // ABC 

11 Amazing New JavaScript Features in ES13

This guide will bring you up to speed with all the latest features added in ECMAScript 13. These powerful new features will modernize your JavaScript with shorter and more expressive code.

Ayibatari Ibaba is a software developer with years of experience building websites and apps. He has written extensively on a wide range of programming topics and has created dozens of apps and open-source libraries.

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4 Ways to Remove Character from String in JavaScript

Looking to remove the character from string in JavaScript? Let’s discuss remove method details in this post.

Using substring() method

JavaScript substring() method retrieves the characters between two indexes and returns a new substring.

Two indexes are nothing but startindex and endindex.

Let’s try to remove the first character from the string using the substring method in the below example.

function removeFirstCharacter() < var str = 'tracedynamics'; str = str.substring(1); console.log(str); >Output: racedynamics 

Now let’s remove the last character from the string using the substring method in the below example.

function removeLastCharacter() < var str = 'tracedynamics'; str = str.substring(0,str.length-1); console.log(str); >Output: tracedynamic 

the length property is used to determine the last element position.

As per the output above, you can see that specified first and last characters are removed from the original string.

With substr() method

substr() method will retrieve a part of the string for the given specified index for start and end position.

Let’s remove the first character from string using substr function in the below example.

function removeFirstCharacter() < var str = 'tracedynamics'; str = str.substr(1); console.log(str); >Output: racedynamics 

Now let’s see how to remove the last character from string using substr function in the below example.

function removeLastCharacter() < var str = 'tracedynamics'; str = str.substr(0,str.length-1); console.log(str); >Output: tracedynamic 

using below JavaScript code, we can also remove whitespace character from a string.

function removeWhiteSpaceCharacter() < var str = 'tracedynamics '; str = str.substr(0,str.length-1); console.log(str); >Output: tracedynamics 

As you can see from the above function, in the input string value there is whitespace at the end of the string which is successfully removed in the final output.

Using slice() method

slice() method retrieves the text from a string and delivers a new string.

Let’s see how to remove the first character from the string using the slice method.

function removeFirstCharacter() < var str = 'tracedynamics'; str = str.slice(1); console.log(str); >Output: racedynamics 

Now let’s remove the last character from string using the slice method.

function removeLastCharacter() < var str = 'tracedynamics'; str = str.slice(0,str.length-1); console.log(str); >Output: tracedynamic 

Using replace() method

replace() method is used to replace a specified character with the desired character.

This method accepts two arguments or parameters.

The first argument is the current character to be replaced and the second argument is the new character which is to be replaced on.

Let’s see how to replace the first character in a string using the replace function.

function replaceFirstCharacter() < var str = 'tracedynamics'; str = str.replace('t','T'); console.log(str); >Output: Tracedynamics 

Now let’s replace the last character in JavaScript string using replace function.

function replaceLastCharacter() < var str = 'tracedynamics'; str = str.replace('s','S'); console.log(str); >Output: tracedynamicS 

Now let’s replace specified character in a string using the replace method.

function replaceCharacter() < var str = 'tracedynamics'; str = str.replace('d','D'); console.log(str); >Output: traceDynamics 

Also we can apply regular expression(regex)in the replace method to replace any complex character or special character in the string.

Regular expressions(regex) are also useful when dealing with a line break, trailing whitespace, or any complex scenarios.

Using above JavaScript methods, we can also remove characters on string array, line break, trailing whitespace, empty string, Unicode character, double quotes, extra spaces, char, parenthesis, backslash

We can remove multiple characters by giving the specified index for start and end position.

To conclude this tutorial, we covered various types of implementation to remove a character from string using JavaScript.

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