ASP.NET WebApi OData对DTO的支持

Question

我有Project实体和ProjectDTO.我正在尝试创建一个WebAPI控制器方法,可以获取并返回ProjectDTO并使其支持OData.

问题是我正在使用可以使用Project实体而不是Project DTO查询数据库的ORM.有什么方法可以根据ProjectDTO从OData应用过滤/排序/分页到Project实体查询？

public ODataQueryResult<ProjectDTO> GetProjects(ODataQueryOptions<ProjectDTO> query)
{
    var context = new ORM_Context();

    var projects = context.Projects; // IQueryable<Project>
    var projectDtos = query.ApplyTo(projectDTOs)); // <-- I want to achieve something similar here
    var projectDTOs =
        projects.Select(
            x =>
            new ProjectDTO
                {
                    Id = x.Id,
                    Name = x.Name
                });

    var projectsQueriedList = projectDtos.ToList();

    var result = new ODataQueryResult<ProjectDTO>(projectsQueriedList, totalCount);

    return result;
}

Answer 1

像这样的东西（我没有尝试编译它）

using(var dataContext = new ORM_Context())
{
    var projects = dataContext.Projects; // IQueryable<Project>

    //Create a set of ODataQueryOptions for the internal class
    ODataModelBuilder modelBuilder = new ODataConventionModelBuilder();
    modelBuilder.EntitySet<Project>("Project"); 
    var context = new ODataQueryContext(
         modelBuilder.GetEdmModel(), typeof(Project));
    var newOptions = new ODataQueryOptions<Project>(context, Request);

    var t = new ODataValidationSettings() { MaxTop = 25 };
    var s = new ODataQuerySettings() { PageSize = 25 };
    newOptions.Validate(t);
    IEnumerable<Project> internalResults =
        (IEnumerable<Project>)newOptions.ApplyTo(projects, s);

    int skip = newOptions.Skip == null ? 0 : newOptions.Skip.Value;
    int take = newOptions.Top == null ? 25 : newOptions.Top.Value;

    var projectDTOs =
            internalResults.Skip(skip).Take(take).Select(x =>
                new ProjectDTO
                    {
                        Id = x.Id,
                        Name = x.Name
                    });

    var projectsQueriedList = projectDtos.ToList();
    var result = new ODataQueryResult<ProjectDTO>(
        projectsQueriedList, totalCount);
    return result;
}