How can I implement Regexp in TypeScript?
My Example:
var trigger = "2" var regex = new RegExp('^[1-9]\d{0,2}$', trigger); // where I have exception in Chrome console 4 Answers
I think you want to test your RegExp in TypeScript, so you have to do like this:
var trigger = "2", regexp = new RegExp('^[1-9]\d{0,2}$'), test = regexp.test(trigger); alert(test + ""); // will display true You should read MDN Reference - RegExp, the RegExp object accepts two parameters pattern and flags which is nullable(can be omitted/undefined). To test your regex you have to use the .test() method, not passing the string you want to test inside the declaration of your RegExp!
Why test + ""? Because alert() in TS accepts a string as argument, it is better to write it this way. You can try the full code here.
You can do just:
var regex = /^[1-9]\d{0,2}$/g regex.test('2') // outputs true In typescript, the declaration is something like this:
const regex : RegExp = /.+\*.+/; using RegExp constructor:
const regex = new RegExp('.+\\*.+'); const regex = /myRegexp/ console.log('Hello myRegexp!'.replace(regex, 'World')) // = Hello World!The Regex literal notation is commonly used to create new instances of RegExp
regex needs no additional escaping v / regex / gm ^ ^ ^ start end optional modifiers As others sugguested, you can also use the new RegExp('myRegex') constructor.
But you will have to be especially careful with escaping:
regex: 12\d45 matches: 12345 Extra excape because it is part of a string v const regex = new RegExp('12\\d45') const equalRegex = /12\d45/ 
