How to check if contains all keywords in any order of string? RegExp Javascript

Question

I want to check if a string have all input keywords in any order of the string. In much cases, the keywords are in any order, but exists in string.

Example(this is what I expect):

// Same order and have all keywords
"Hello world!".contains( "hello world" )       // true

// Same order and have all keywords
"Hello all in the world!".contains( "hello world" )       // true

// Any order but have all keywords
"Hello world!".contains( "world hello" )       // true

// Same order and all keywords
"Hello world!".contains( "worl hell" )         // true

// Have all keywords in any order
"Hello world!".contains( "world" )             // true

// No contains all keywords
"Hello world!".contains( "where you go" )      // false

// No contains all keywords
"Hello world!".contains( "z" )                 // false

// No contains all keywords
"Hello world!".contains( "z1 z2 z3" )          // false

// Contains all keywords in any order
"Hello world!".contains( "wo" )                // true

I try with:

/(?=\bhello\b)(?=\bworld\b)/i.test("hello world")      // false
/(?=.*?hello.*?)(?=.*?world.*?)/i.test("hello world")  // false
/^(?=\bhello\b)(?=\bworld\b).*?$/i.test("hello world") // false

I created some functions like:

// escape string to use in regexp
String.prototype.escape = function () {
    return this.replace(/[\-\[\]\/\{\}\(\)\*\+\?\.\\\^\$\|]/g, "\\$&")
};
// check if empty string
String.prototype.isEmpty = function () {
    return this.length === 0;
};
// check if contain keywords...
String.prototype.contains = function (keywords) {
    var value  = '^(?=\\b' + keywords
        .escape()
        .replace(/(^\s+|\s+$)/ig, '')
        .replace(/\s+/, ' ')
        .split(/\s+/)
        .join('.*?)(?=.*?') + ').*$',
    reg = new RegExp(value, 'i'),
    text = this;
    return reg.test( this );
};

Thanks

Answer 1

You mean an unordered list of keywords: Regex - match multiple unordered words in a string , but removing the last \\b part of each regex token

/(?=.*?\bhello)(?=.*?\bworld).*/i

With these type of regex all your test should pass now.

Check it in http://regexr.com/3f3ru

i makes it to ignore case sensitive, in case you need to check also Hello , wOrld , etc

Answer 2

The answer from IG Pascual shows how to construct a regex that solves the OP's problem. Below is working code demonstrating how to build such regexes dynamically, passing all the test cases from the OP.

 function buildRegEx(str, keywords){ return new RegExp("(?=.*?\\\\b" + keywords .split(" ") .join(")(?=.*?\\\\b") + ").*", "i" ); } function test(str, keywords, expected){ var result = buildRegEx(str, keywords).test(str) === expected console.log(result ? "Passed" : "Failed"); } // Same order and have all keywords test("Hello world!", "hello world", true); // Same order and have all keywords test("Hello all in the world!", "hello world", true); // Any order but have all keywords test("Hello world!", "world hello", true); // Same order and all keywords test("Hello world!", "worl hell", true); // Have all keywords in any order test("Hello world!", "world", true); // No contains all keywords test("Hello world!", "where you go", false); // No contains all keywords test("Hello world!", "z", false); // No contains all keywords test("Hello world!", "z1 z2 z3", false); // Contains all keywords in any order test("Hello world!", "wo", true);

Answer 3

An alternative to the lookahead-based option would be:

String.prototype.contains = function (keywordsStr) {
    var keywords = keywordsStr.split(/\s+/);
    return keywords.every(function(keyword)) {
        var reg = new RegExp(keyword.escape());
        return reg.test(this);
    }, this);
};

Answer 4

String.prototype.contains = function(string){    
    var keywords = string.split(" ");
    var contain = true;

    for(var i = 0; i < keywords.length && contain; i++){
        if(keywords[i] == "") continue;

        var regex = new RegExp(keywords[i], "i");
        contain = contain && regex.test(this);
    }

    return contain;
}

Answer 5

It's easy way to use .match() method to string. You can try this

Example:

var re = /(hello|world)/i;
var str = "Hello world!"; 
console.log('Do we found something?', Boolean(str.match(re)));

// for other
var re = /(hello|world)/i;       // true
var re = /(world|hello)/i;       // true
var re = /(worl|hell)/i;         // true
var re = /(this|is|my|world)/i;  // true
var re = /(where|you|go)/i;      // false
var re = /(z)/i;                 // false
var re = /(z1|z2|z3)/i;          // false
var re = /(wo)/i;                // true

Answer 6

result.filter(camp => search.map(keyword => camp.name.includes(keyword)).reduce((acc, curr) => acc && curr, true));