You cannot change a variable’s type in TypeScript, that’s just the opposite TS was made for. Instead, you can declare a variable as “any”, which would be equivalent to a classic “var” variable in JS, untyped. Once a variable is declared, you will not be able to retype it. What you could do, however, is … Read more
According to the NgClass API docs, Angular 2 will accept a string, an Array, or an Object/map as the expression to NgClass. Or, of course, you could specify a function that returns one of those. import {Component, CORE_DIRECTIVES} from ‘angular2/angular2’ @Component({ selector: ‘my-app’, directives: [CORE_DIRECTIVES], template: ` <div> <h2>{{title}}</h2> <div ngClass=”gray-border purple”>string of classes</div> <div … Read more
Visual Studio 2015 supports tsconfig files starting with Typescript version 1.8. Create tsconfig.json file at the root of your project and add experimentalDecorators compiler option. Example: { “compileOnSave”: true, “compilerOptions”: { “module”: “commonjs”, “sourceMap”: true, “experimentalDecorators”: true } } For older versions: https://github.com/Microsoft/TypeScript/issues/3934 If you have a project file, tsconfig will not be honored. the … Read more
There should be a cleaner way to do this: var element = <HTMLInputElement> document.getElementById(“btnExcel”); element.disabled = true; Or if you prefer a one liner: (<HTMLInputElement> document.getElementById(“btnExcel”)).disabled = true; It seems getElementById and the like should be a generic method and accept a type parameter. That said, a generic method wouldn’t give you anything that typecasting … Read more
To define a class with an index signature, just write the index signature in the class: interface IRawParams { [key: string]: any } class Foo implements IRawParams { [k: string]: any; }
I was having this same error. I added the following tsconfig.json file to my project root, restarted VSCode and it finally went away: { “compilerOptions”: { “emitDecoratorMetadata”: true, “experimentalDecorators”: true, “module”: “amd”, “target”: “ES6″ } } UPDATE: I’ve noticed that sometimes VS Code will not suppress this warning until you add a “files” array in … Read more
You need the declare global declare global { interface Window { fetch:(url: string, options?: {}) => Promise<any> } } This works then: window.fetch(‘/blah’).then(…);
You can always use Array.prototype.filter in this way: const arr = [1, 2, 3]; const [notFoundItem] = arr.filter(id => id === 4); // will contain undefined const [foundItem] = arr.filter(id => id === 3); // will contain 3 Edit My answer applies to FirstOrDefault and not to SingleOrDefault. SingleOrDefault checks if there is only one … Read more
Use re-exporting to create an external module that groups and exposes types from other modules: // Classes/Animals.ts export * from ‘.\Animals\Mammals’; export * from ‘.\Animals\Reptiles’; Then import the types from the new module as usual: // app.ts import * as Animals from ‘.\Classes\Animals’ let dog: Animals.Dog; let snake: Animals.Snake; Or // app.ts import { Dog, … Read more
Yes, what you’re looking for is possible and works nicely. It appears as though you have the dependencies right. I think you are missing only the following, which needs to be at the beginning of your top level typescript or JavaScript file. Specifically, these need to be prior to the first line is that loads … Read more