Question

I would like to know how to match a string against an array of regular expressions.
I know how to do this looping through the array.
I also know how to do this by making a long regular expression separated by |
I was hoping for a more efficient way like

if (string contains one of the values in array) {

For example:

string = "the word tree is in this sentence";  
array[0] = "dog";  
array[1] = "cat";  
array[2] = "bird";  
array[3] = "birds can fly";  

In the above example, the condition would be false.
However, string = "She told me birds can fly and I agreed" would return true.

Answer 1

How about creating a regular expression on the fly when you need it (assuming the array changes over time)

if( (new RegExp( '\\b' + array.join('\\b|\\b') + '\\b') ).test(string) ) {
  alert('match');
}

demo:

string = "the word tree is in this sentence"; 
var array = [];
array[0] = "dog";  
array[1] = "cat";  
array[2] = "bird";  
array[3] = "birds can fly";  

if( (new RegExp( '\\b' + array.join('\\b|\\b') + '\\b') ).test(string) ){
    alert('match');
}
else{
    alert('no match');
}

---

For browsers that support javascript version 1.6 you can use the some() method

if ( array.some(function(item){return (new RegExp('\\b'+item+'\\b')).test(string);}) ) {
 alert('match');
}

demo:

string = "the word tree is in this sentence"; 
var array = [];
array[0] = "dog";  
array[1] = "tree";  
array[2] = "bird";  
array[3] = "birds can fly";  

if ( array.some(function(i){return (new RegExp('\\b'+i+'\\b')).test(string);}) ) {
 alert('match');
}