c# - 如何在最小起订量存储库中执行表达式？

Question

我有具有函数声明的 IGeneric 存储库

T FindBy(Expression<Func<T, bool>> predicate);

在通用存储库类中

public T FindBy(System.Linq.Expressions.Expression<Func<T, bool>> predicate)
    {
        return _dbset.FirstOrDefault(predicate);
    }

并拥有单元测试类，创建一个模拟存储库并将数据初始化到模拟数据库中

[TestClass]
public class ServiceTest
{
    private IClientRepository mockClientRepository;
public ServiceTest()
    {
        IList<ClientData> client = new List<ClientData>
            {
                new ClientData{ Name= "Mike", Address ="Uk" },
                new ClientData{ Name= "Jane", Address ="US" },
            };
         Mock<IClientRepository> _mockRepository = new Mock<IClientRepository>();
        _mockRepository.Setup(m => m.FindBy(It.IsAny<Expression<Func<ClientData, bool>>>())).Returns((string apiClient) =>
        {
            var data = client.Where(x => x.Hash == apiClient).FirstOrDefault();
            return data;
        });
this.mockClientRepository = _mockRepository.Object;
} 
[TestMethod]
public void IsDataFindByName()
    {
        ClientData testResult = this.mockClientRepository.FindBy(i => i.Name== "Mike");
        Assert.IsNotNull(testResult);
    }

我在运行测试时发现异常

Additional information: Object of type 'System.Linq.Expressions.Expression`1[System.Func`2[Adminportal.Entities.ClientData ,System.Boolean]]' cannot be converted to type 'System.String'.

我不知道怎么传，

Answer 1

参数Returns方法期望其参数与模拟方法的参数具有相同的类型。您使用 .Returns((string apiClient)什么时候Expression<Func<ClientData, bool>>是期待。只需将其更改为:

.Returns((Expression<Func<ClientData, bool>> expression) =>
{
    var data = client.Where(expression.Compile()).FirstOrDefault();
    return data;
});