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I have tried to create an extension method in TypeScript based on this discussion (https://github.com/Microsoft/TypeScript/issues/9), but I couldn't create a working one.
Here is my code,
namespace Mynamespace { interface Date { ConvertToDateFromTS(msg: string): Date; } Date.ConvertToDateFromTS(msg: string): Date { //conversion code here } export class MyClass {} } but its not working.
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Just like object-oriented languages such as Java and C#, TypeScript classes can be extended to create new classes with inheritance, using the keyword extends . In the above example, the Employee class extends the Person class using extends keyword.
You can use extension methods to extend a class or interface, but not to override them. An extension method with the same name and signature as an interface or class method will never be called. At compile time, extension methods always have lower priority than instance methods defined in the type itself.
Select File > New > Project and select Visual C# and Console Application as shown below. Add the reference of the previously created class library to this project. In the above code, you see there is a static class XX with a method, NewMethod.
You need to change the prototype:
interface Date { ConvertToDateFromTS(msg: string): Date; } Date.prototype.ConvertToDateFromTS = function(msg: string): Date { // implement logic } let oldDate = new Date(); let newDate = oldDate.ConvertToDateFromTS(TS_VALUE); Though it looks like you want to have a static factory method on the Date object, in which case you better do something like:
interface DateConstructor { ConvertToDateFromTS(msg: string): Date; } Date.ConvertToDateFromTS = function(msg: string): Date { // implement logic } let newDate = Date.ConvertToDateFromTS(TS_VALUE); If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
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