I've two variables:
var input = "[email protected]";
var preferredPatterns = ["*@gmail.com", "*@yahoo.com", "*@live.com"];
Want to match the input with preferred pattern array. If any of the patterns matches I've to do certain task (in this example, input is a definite match). How can I match against an array of pattern in javascript?
You can compile your patterns (if they are valid regular expressions) into one for performance:
var masterPattern = new RegExp(patterns.join('|'));
Putting it all together:
var input = '[email protected]';
var preferredPatterns = [
".*@gmail.com$",
".*@yahoo.com$",
".*@live.com$"
];
var masterPattern = new RegExp(preferredPatterns.join('|'));
console.log(masterPattern.test(input));
// true
masterPattern would be even faster, as you can refactor the .* -- $ bit for more speed).
SyntaxError: Invalid regular expression: /*@qa-server5.com$|*@qa-server4.com$/*. If you want to allow your users to input patterns, then you also need a method to transform them into valid regular expressions (escaping any dangerous characters, and turning * into .*, for starters). Otherwise, just write correct regular expression patterns in the first place.You need to use RegExp constructor while passing a variable as regex.
var input = '[email protected]';
var preferredPatterns = [".*@gmail\\.com$", ".*@yahoo\\.com$", ".*@live\\.com$"];
for (i=0; i < preferredPatterns.length;i++) {
if(input.match(RegExp(preferredPatterns[i]))) {
console.log(preferredPatterns[i])
}
}
Dot is a special meta-character in regex which matches any character. You need to escape the dot in the regex to match a literal dot.
As @zerkms said, you could use the below list of patterns also.
var preferredPatterns = ["@gmail\\.com$", "@yahoo\\.com$", "@live\\.com$"];
.* from regular expressions and nothing will change.
Try this helper function:
/**
* Returns an integer representing the number of items in the patterns
* array that contain the target string text
*/
function check(str, patterns) {
return patterns.reduce(function (previous, current) {
return previous + (str.indexOf(current) == -1 ? 0 : 1);
}, 0);
}
check("[email protected]", ["@gmail.com", "@yahoo.com", "@live.com"]; // returns 1
check("[email protected]", ["@gmail.com", "@yahoo.com", "@live.com"]; // returns 0
If you want a general approach to matching against a list of regular expressions then some version of Avinash Raj's answer will work.
Based on the fact that you are specifying certain domains, you might want to match any valid email address using the regex here, and if it matches then check if the domain is a preferred one. There are a number of different ways you could do that of course. Here's just a simple example, splitting on the @ and using jQuery.inArray() to check if the domain is preferred.
var preferredDomains = ["gmail.com", "yahoo.com", "live.com"];
function isValid(inputVal) {
var re = /^([\w-]+(?:\.[\w-]+)*)@((?:[\w-]+\.)*\w[\w-]{0,66})\.([a-z]{2,6}(?:\.[a-z]{2})?)$/i;
return re.test(inputVal) && $.inArray(inputVal.split('@')[1], preferredDomains) > -1;
}
The advantage here is that the underlying regex doesn't change, just the much easier to read/maintain list of domains. You could tweak this to capture the domain in a group, instead of using split().
No regexp you may do as follows;
function matchPattern(xs, [y,...ys]){
function helper([x,...xs]){
return "*" + xs.join('') === y ? true
: xs.length ? helper(xs)
: false;
}
return helper(xs) ? y
: ys.length ? matchPattern(xs,ys)
: "No Match..!";
}
var input = "[email protected]",
preferredPatterns = ["*@yahoo.com", "*@live.com", "*@gmail.com"];
result = matchPattern(input, preferredPatterns);
console.log(result);
preferredPatterns.forEach(function(element, index){
if(input.match('/'+element) != null){
console.log('matching ' + element)
}
})
you can write your custom logic if a string matches any pattern.
You may iterate through array and then use regex to compare with individual items.
[email protected]is not a string, either.