Split() Detailed Explanation

Requirement: js takes out each element according to the comma in the string and puts it in the array

split()The method splits a String object into an array of substrings using the specified delimiter string , and uses a specified split string to determine the position of each split.

const str = 'The quick brown fox jumps over the lazy dog.';

const words = str.split(' ');
console.log(words[3]);
// Expected output: "fox"

const chars = str.split('');
console.log(chars[8]);
// Expected output: "k"

const strCopy = str.split();
console.log(strCopy);
// Expected output: Array ["The quick brown fox jumps over the lazy dog."]

grammar

str.split([separator[, limit]])

Warning: If an empty string (") is used as the delimiter, the string is not between each user-perceived character (graphic veneer cluster), nor between each Unicode character (code point), but between between each UTF-16 code unit. This destroys surrogate pairs. See also how do you get a string to a character array in javascript

parameter

separator

Specifies a string representing the point at which each split should occur. separator Can be a string or regular expression . If the plain text delimiter contains more than one character, the whole string must be found to represent the split point. If the delimiter is omitted or present in str, the returned array contains one element consisting of the entire string. If delimiter is the empty string, str is returned as an array of each character in the original string.

limit

An integer limiting the number of splits returned. When this parameter is provided, the split method splits the string at each occurrence of the specified delimiter, but stops when a limit entry has been placed into the array. If the end of the string is reached before the specified limit is reached, it may still contain fewer entries than the limit. The remaining text is not returned in the new array.

return value

Returns an Array of the source string separated by the position of the delimiter

describe

When a delimiter is found, it is removed from the string and an array of substrings is returned. If no delimiter is found or omitted, the array contains one element consisting of the entire string. If delimiter is the empty string, convert str to a character array. If the delimiter appears at the beginning or end of the string, or both, start and end with the empty string, end or both, respectively. Thus, if the string consists of only one instance of separator, the array consists of two empty strings.

If the delimiter is a regular expression containing capturing parentheses, the results of the capturing parentheses (including any undefined results) will be concatenated into the output array each time the delimiter matches. However, not all browsers support this feature.

Remark: split() returns an array containing an empty string instead of an empty array when the string is empty, or an empty array if both string and delimiter are empty strings.

example

use split()

The following example defines a function: split a string into an array of strings according to the specified delimiter. After delimiting the string, the function outputs the original string information, the delimiter used, the number of returned array elements, and returns all elements in the array in turn.

function splitString(stringToSplit, separator) {
  var arrayOfStrings = stringToSplit.split(separator);

  console.log('The original string is: "' + stringToSplit + '"');
  console.log('The separator is: "' + separator + '"');
  console.log("The array has " + arrayOfStrings.length + " elements: ");

  for (var i=0; i < arrayOfStrings.length; i++)
    console.log(arrayOfStrings[i] + " / ");
}

var tempestString = "Oh brave new world that has such people in it.";
var monthString = "Jan,Feb,Mar,Apr,May,Jun,Jul,Aug,Sep,Oct,Nov,Dec";

var space = " ";
var comma = ",";

splitString(tempestString, space);
splitString(tempestString);
splitString(monthString, comma);