通过特定where子句在C#中创建泛型方法

Generic constraints 将由和合并,所以 where T : IBaseModel, IList<IBaseModel> 方法 T 两者都应该实现 IBaseModel IList<IBaseModel> .

您需要创建两个方法:

public async Task<T> Get<T>(string url) where T : IBaseModel
public async Task<IList<T>> GetList<T>(string url) where T : IBaseModel

您可以使用另一个同时实现iAsseModel和IList的类,然后将IList约束到这个类。

public class DerivedModel : IBaseModel, IList<IBaseModel>
{
    private int _size;
    private IBaseModel[] _items=new IBaseModel[1000];
    private int _version;
    public int Id { get; set; }
    public IEnumerator<IBaseModel> GetEnumerator()
    {
        throw new NotImplementedException();
    }

    IEnumerator IEnumerable.GetEnumerator()
    {
        return GetEnumerator();
    }
...
}

一般方法是:

public async Task<T> Get<T>(string url) where T : DerivedModel 
    {
        return await Task<T>.Factory.StartNew(() =>
        {
            var derivedModel = new DerivedModel() {new BaseModel() {Id = 1}};
            return (T) derivedModel;
        });
    }

其中IBaseModel和BaseModel可以是:

public interface IBaseModel
{
    int Id { get; set; }
}

public class BaseModel : IBaseModel
{
    public int Id { get; set; }
}

用法:

var inheritance=new Inheritance();
var result = await inheritance.Get<DerivedModel>("aaa");
textBox1.Text = result[0].Id.ToString();