在Typescript中创建通用方法装饰器

也许是这样的:

interface PromiseDescriptorValue{
  (...args: any[]): Promise;
}

export function fetchJson(): any
{
    return (
        target: Object,
        propertyKey: string,
        descriptor: any): TypedPropertyDescriptor> => 
        {
        const oldMethod = descriptor.value;

        descriptor.value = function(...args: any[]) 
        {
            return oldMethod.apply(this, args).then((res: Response) => res.json());
        };

        return descriptor;
        };
}

class C 
{
    @fetchJson()
    foo(args) 
    {
        //....
    }
}