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The JavaScript String object is used to store and process text.
The JavaScript String object is a global object used to store strings.
The string can be any text within double quotes or single quotes:
var msg = "Hello world"; var msg = 'Hello world';
Unlike some other languages, JavaScript does not distinguish between single quotes and double quotes.
The index of JavaScript strings is zero: the first element of the string is located at index 0, the second element is1, and so on.
You can find it in ourIn the JavaScript String tutorialLearn more about String.
The following table lists the properties of the String object:
| Properties | Description |
|---|---|
| constructor | Return the function that creates the prototype of the String object |
| length | Return the length of the string |
| prototype | Allows you to add new properties and methods to the object |
The following table lists the methods of the String object:
| Method | Description |
|---|---|
| charAt() | Return the character at the specified index |
| charCodeAt() | Return the Unicode of the character at the specified index |
| concat() | Concatenate two or more strings and return a new string |
| endsWith() | Check if the string ends with the specified substring |
| fromCharCode() | Convert a Unicode value to a character |
| includes() | Check if the string contains the specified substring |
| indexOf() | Return the index of the first occurrence of the specified value in the string |
| lastIndexOf() | Return the index of the last occurrence of the specified value in the string |
| localeCompare() | Compare two strings in the current language environment |
| match() | Match the string with a regular expression and return an array of all matches |
| repeat() | Return a new string containing a specified number of copies of the original string |
| replace() | Replace the string or pattern that appears in the string with another string and return a new string without modifying the original string |
| search() | Search the string using regular expressions and return the index of the first match |
| slice() | Extract a part of the string and return it as a new string |
| split() | Split the string into an array of substrings |
| startsWith() | Check if the string starts with the specified substring |
| substr() | Extract a portion of the string starting from the index and following characters |
| substring() | Extract the string between the start index and the end index |
| toLocaleLowerCase() | Convert the string to lowercase letters based on the current language environment of the host |
| toLocaleUpperCase() | Convert the string to uppercase letters based on the current language environment of the host |
| toLowerCase() | Convert the string to lowercase letters |
| toString() | Return the value of the String object |
| toUpperCase() | Convert the string to uppercase letters |
| trim() | Remove whitespace from the beginning and end of the string |
| valueOf() | Return the original value of the String object |
Note:All string methods return a new value. They do not change the original variable.