方法“ProjectTo”沒有重載需要 0 arguments

Question

錯誤

    Severity    Code    Description Project File    Line    Suppression State
    Error   CS1501  No overload for method 'ProjectTo' takes 0 arguments

C#

       public static async Task<PagedResult<U>> GetPagedAsync<T, U>(this IQueryable<T> query, int page, int pageSize) where U : class
    {

        var result = new PagedResult<U>();
        result.CurrentPage = page;
        result.PageSize = pageSize;
        result.RowCount = await query.CountAsync();

        var pageCount = (double)result.RowCount / pageSize;
        result.PageCount = (int)Math.Ceiling(pageCount);

        var skip = (page - 1) * pageSize;
        result.Results = await query.Skip(skip)
                                     .Take(pageSize)
                                     .ProjectTo<U>()
                                     .ToListAsync();
        return result;
    }

將 core 6.0 遷移到 core 7.0 后出現上述錯誤

Answer 1

AutoMapper.QueryableExtensions提供的ProjectTo方法需要IConfigurationProvider 。 您可以使用IMapper中的一個或嘗試直接解析IConfigurationProvider ：

IMapper mapper = ...; // resolve from the DI

var result = query
   .ProjectTo<SomeClass>(mapper.ConfigurationProvider)
   // ...
   ;

要么

IConfigurationProvider cfg = ...; // resolve from the DI

var result = query
   .ProjectTo<SomeClass>(cfg)
   // ...
   ;