javascript string delete

JavaScript is a programming language widely used in web development, of which strings are a very important part. In order to better use and manipulate strings, Javascript provides a series of built-in string methods. This article will focus on the method of JavaScript string deletion.

1. The concept of JavaScript string deletion

In Javascript, a string can be represented as a series of characters, and each character has a corresponding index number in the string. Deleting a character from a string means removing that character from the string and moving the remaining characters one position to the left.

2. JavaScript string deletion method

1. Use the substring() method

The JavaScript substring() method can be used to delete a specified period of characters in the string. The syntax is as follows:

string.substring(start, end)

where start is the starting position of the characters that need to be deleted, and end is the end position of the characters that need to be deleted. For example, the following code removes characters with indexes 2 through 6 in a string:

var str = "hello world";
var newStr = str.substring(2, 7);
console .log(newStr); // "llo w"

2. Use the slice() method

JavaScript's slice() method can also be used to delete a specified period of characters in a string. The syntax is as follows:

string.slice(start, end)

where start is the starting position of the characters that need to be deleted, and end is the end position of the characters that need to be deleted. For example, the following code removes characters with indices 2 through 6 in a string:

var str = "hello world";
var newStr = str.slice(0, 2) str.slice(7 );
console.log(newStr); // "he world"

3. Use the replace() method

JavaScript's replace() method can be used to replace strings Replace one character with another character, and can also be used to delete a character in a string. The syntax is as follows:

string.replace(searchvalue, newvalue)

where searchvalue is the character that needs to be replaced or deleted, and newvalue is the replaced character. For example, the following code removes the first "l" character from a string:

var str = "hello world";
var newStr = str.replace("l", "");
console.log(newStr); // "helo world"

4. Use the substr() method

JavaScript's substr() method can be used to get a string For a string of specified length, the effect of deleting characters can be achieved by specifying the starting position and length. The syntax is as follows:

string.substr(start, length)

where start is the starting position of the characters to be deleted, and length is the number of characters to be deleted. For example, the following code can delete 3 characters starting from index 2 in a string:

var str = "hello world";
var newStr = str.substr(0, 2) str.substr( 5);
console.log(newStr); // "he world"

5. Use the split() method

JavaScript's split() method can split the string into Array, the effect of deleting a string is achieved by deleting elements in the array. The syntax is as follows:

string.split(separator, limit)

where separator is the character used to split the string, and limit is the maximum length of the returned array. For example, the following code removes the first "l" character from a string:

var str = "hello world";
var arr = str.split("");
arr .splice(2, 1);
var newStr = arr.join("");
console.log(newStr); // "helo world"

3. Summary

This article introduces several methods of JavaScript string deletion, including substring(), slice(), replace(), substr(), split(), etc. These methods can help us operate and process strings effectively and are very useful in actual development. If you want to learn more about JavaScript, please continue to follow our articles.

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