如何从字符串中删除列表短语？

Question

I want to check a string for a list of phrases. If those phrases exist I want to remove them and return a new string.

For Example:
String: Lower Dens - Propagation (Official Music Video)
Result: Lower Dens - Propagation

This is what I have so far, but it does not work. This would work for single words, but not phrases. I am using underscore for the each loop, but I am open to any solution.

formatVideoTitle = function(videoTitle){
    var phrases = [
        '(Official Music Video)',
        '(Official Video)',
        '(Music Video)'
    ],
    newVideoTitle = videoTitle;

    _.each(phrases, function(phrase){
        newVideoTitle.replace(phrase, '');
    });

    return newVideoTitle;
};

Answer 1

set newVideoTitle to the result of the replace operation it works. I would make a jsfiddle but am too lazy to include underscore.

heres a fiddle

formatVideoTitle = function(videoTitle){
    var phrases = [
        '(Official Music Video)',
        '(Official Video)',
        '(Music Video)'
    ],
    newVideoTitle = videoTitle;

    _.each(phrases, function(phrase){
        newVideoTitle = newVideoTitle.replace(phrase, '');
    });

    return newVideoTitle;
};

Answer 2

formatVideoTitle = function(videoTitle){
    var phrases = [
        '(Official Music Video)',
        '(Official Video)',
        '(Music Video)'
    ],
    newVideoTitle = videoTitle;

    _.each(phrases, function(phrase){
        newVideoTitle = newVideoTitle.replace(phrase, '');
    });

    return newVideoTitle;
};

Edit: The change is

newVideoTitle = newVideoTitle.replace(phrase, '');

'replace' returns the result of the operation, you you'll need to pass it back. Also beware that this will only match the first occurance of that string, if the phrase appears multiple times then you'll need to use regex to replace all instances.

Edit 2: Example of use of regex to replace all instances:

newVideoTitle = newVideoTitle.replace(new RegExp(phrase, 'g'), '');

Answer 3

replace returns a value, so you need to assign the replaced variable to a new variable (or the same one):

_.each(phrases, function(phrase) {
  newVideoTitle = newVideoTitle.replace(phrase, '');
});

DEMO

Answer 4

I think the problem is with the replace statement. If you assign the result to newVideoTitle than it will work.

newVideoTitle = newVideoTitle.replace(phrase, '');

Answer 5

Due to the lack of "replaceAll" in JavaScript, I like to use "split/join".

formatVideoTitle = function(videoTitle){
    ...
    _.each(phrases, function(phrase){
        newVideoTitle.split(phrase).join('');
    });

    return newVideoTitle;
};

If you know that the phrase is always at the back of the string, you could also use:

formatVideoTitle = function(videoTitle){
    ...
    _.each(phrases, function(phrase){
        newVideoTitle = newVideoTitle.slice(0, newVideoTitle.indexOf(phrase));
    });

    return newVideoTitle;
};

Answer 6

If you don't mind not using underscore for this, JavaScript has a relatively easy means of achieving the same with regular expressions (though there's a little complexity in the creation of that regular expression):

formatVideoTitle = function (title) {
    var phrases = [
        '(Official Music Video)',
        '(Official Video)',
        '(Music Video)'],
    // creating Regular Expression object, by joining the phrases together with '|'
    // characters (an 'OR' relationship) to create a string, prefacing the '(' and ')'
    // characters with a double escape (to escape them in the created RegExp), and
    // wrapping that created string in '(' and ')' to create a matching group:
        reg = new RegExp('(' + phrases.join('|').replace(/(\(|\))/g, function(a){
            return '\\' + a;
        }) + ')', 'gi');
    // returning the amended title:
    return title.replace(reg, '');
}

console.log(formatVideoTitle("Lower Dens - Propagation (Official Music Video)"));

JS Fiddle demo .

References:

• Array.prototype.join() .
• JavaScript Regular Expressions .
• RegExp() .
• String.prototype.replace() .