property-names.ts

type NonFunctionPropertyNames<T> = { [K in keyof T]: T[K] extends Function ? never : K }[keyof T];

export function getPropertyNames<T>(defaultInstance: T): NonFunctionPropertyNames<T>[] {
	const memberNames = Object.getOwnPropertyNames(defaultInstance); // get all members of the instance
	const propertyNames = memberNames.filter(x => typeof (defaultInstance as any)[x] != "function"); // filter out functions
	return propertyNames as NonFunctionPropertyNames<T>[]; // cast as array of string union of non-function properties (ideally would be a string typed tuple but can't be done yet)
}

export function createFromObject<T>(constructor: { new(): T }, parameters: Partial<T>): T {
	const newInstance = new constructor();
	const propertyNames = getPropertyNames(newInstance);
	for (let propertyName of propertyNames)
		(<any>newInstance)[propertyName] = (<any>parameters)[propertyName];
	return newInstance;
}

export function createFromObjects<T>(constructor: { new(): T }, parametersArray: Partial<T>[]): T[] {
	return parametersArray.map(parameters => createFromObject<T>(constructor, parameters));
}