Javascript：返回字符串中的最后一个单词

Question

right to it:

I have a words string which has two words in it, and i need to return the last word. They are seperated by a " ". How do i do this?

function test(words) {

var n = words.indexOf(" ");
var res = words.substring(n+1,-1);
return res;

}

I've been told to use indexOf and substring but it's not required. Anyone have an easy way to do this? (with or without indexOf and substring )

Answer 1

Try this:

you can use words with n word length.

example:

  words = "Hello World";
  words = "One Hello World";
  words = "Two Hello World";
  words = "Three Hello World";

All will return same value: "World"

function test(words) {
    var n = words.split(" ");
    return n[n.length - 1];

}

Answer 2

You could also:

words.split(" ").pop();

Just chaining the result (array) of the split function and popping the last element would do the trick in just one line :)

Answer 3

var data = "Welcome to Stack Overflow";
console.log(data.split(" ").splice(-1));

Output

[ 'Overflow' ]

This works even if there is no space in the original string, so you can straight away get the element like this

var data = "WelcometoStackOverflow";
console.log(data.split(" ").splice(-1)[0]);

Output

WelcometoStackOverflow

Answer 4

You want the last word , which suggests lastIndexOf may be more efficient for you than indexOf . Further, slice is also a method available to Strings .

var str = 'foo bar fizz buzz';
str.slice(
    str.lastIndexOf(' ') + 1
); // "buzz"

See this jsperf from 2011 showing the split vs indexOf + slice vs indexOf + substring and this perf which shows lastIndexOf is about the same efficiency as indexOf , it mostly depends on how long until the match happens.

Answer 5

To complete Jyoti Prakash, you could add multiple separators ( \\s | , ) to split your string (via this post )

Example:

function lastWord(words) {
  var n = words.split(/[\s,]+/) ;
  return n[n.length - 1];
}

Note: regex \\s means whitespace characters : A space character, A tab character, A carriage return character, A new line character, A vertical tab character, A form feed character

snippet

 var wordsA = "Hello Worlda"; // tab var wordsB = "One Hello\\nWorldb"; var wordsC = "Two,Hello,Worldc"; var wordsD = "Three Hello Worldd"; function lastWord(words) { var n = words.split(/[\\s,]+/); return n[n.length - 1]; } $('#A').html( lastWord(wordsA) ); $('#B').html( lastWord(wordsB) ); $('#C').html( lastWord(wordsC) ); $('#D').html( lastWord(wordsD) );

 <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> A:<span id="A"></span><br/> B:<span id="B"></span><br/> C:<span id="C"></span><br/> D:<span id="D"></span><br/>

Answer 6

Adding from the accepted answer, if the input string is "Hello World " (note the extra space at the end), it will return '' . The code below should anticipate in case user fat-fingered " " :

var lastWord= function(str) {
  if (str.trim() === ""){
    return 0;
  } else {   
    var splitStr = str.split(' ');
    splitStr = splitStr.filter(lengthFilter);
    return splitStr[splitStr.length - 1];
  }
};

var lengthFilter = function(str){
    return str.length >= 1;
};

Answer 7

Easiest way is to use slice method:-

For example:-

let words = "hello world";
let res = words.slice(6,13);
console.log(res);

Answer 8

/**
 * Get last word from a text
 * @param {!string} text
 * @return {!string}
 */
function getLastWord(text) {
  return text
    .split(new RegExp("[" + RegExp.quote(wordDelimiters + sentenceDelimiters) + "]+"))
    .filter(x => !!x)
    .slice(-1)
    .join(" ");
}

Answer 9

According to me the easiest way is:

lastName.trim().split(" ").slice(-1)

Answer 10

Use split()

function lastword(words){
 array = words.split(' ');

 return array[1]
}

Answer 11

Its pretty straight forward. You have got two words separated by space. Lets break the string into array using split() method. Now your array has two elements with indices 0 and 1. Alert the element with index 1.

var str="abc def";
var arr=str.split(" ");
alert(arr[1]);