如何在 C# 中将 T 类型的 model 转换为“System.Dynamic.ExpandoObject”？

Question

I am trying to add some parameters in the class Job.cs

namespace Test
{
    public class Job
    {
        public int Id { get; set; }
        public int JobId { get; set; }
        public int JobPropertyType { get; set; }
        public string JobValue { get; set; }
    }
}

I am using Dapper for Inserting Data in the tables. Repository.cs

public async Task<T> Add(T entity)
        {
            using (var connection = await _connectionFactory.GetConnectionAsync())
            {
                return await connection.InsertAsync<T>(entity);
            }
        }

I have used DapperMapper for mapping table and data. Mapper.cs

public class JobMapper: ClassMapper<Job>
    {
        public JobMapper()
        {
            Schema("Job");
            Table("Job");
            Map(m => m.JobId).Column("JobId");
            Map(m => m.JobPropertyType).Column("JobPropertyType");
            Map(m => m.JobValue).Column("JobValue");
        }
    }

Here is the JobService.cs

public async Task<Job> InsertJob(int jobId, int jobPropertyType, string jobValue)
        {
            var job = new Job
            {
                JobId = jobId,
                JobPropertyType = jobPropertyType,
                JobValue = jobValue
            };

            return await this.Repository.Add(job);
        }

Another service sending data

public async Task AddJob(int jobId, string snapshot)
        {
            if (!string.IsNullOrEmpty(snapshot))
            {
               await  _jobService.InsertJob(jobId, (int)JobPropertiesEnum.Snapshot, snapshot);
            }

When I am trying to Insert data here, I am getting this exception:

Message=Cannot implicitly convert type 'System.Dynamic.ExpandoObject' to 'Test.Job'. at the time of Inserting (InsertyAsync() in the Repository)

How can I cast it into Dynamic.ExpandoObject?

Answer 1

I assume you are using Dapper-Extensions from here: https://github.com/tmsmith/Dapper-Extensions/tree/master/DapperExtensions

InsertAsync returns a Task<dynamic>, dynamic is an ExpandoObject, so your problem arises when you try to get the return value. The return value is the key of the inserted entity.

You can change your code to something like this (I ddn't have time to test it):

public async Task<T> Add(T entity)
{
    using (var connection = await _connectionFactory.GetConnectionAsync())
    {
        var result = await connection.InsertAsync<T>(entity);
        entity.Id = (int) result;
        return Task.FromResult(entity);
    }
}