C# 枚举到 postgres 枚举

Question

我目前正在使用 postgres 枚举

CREATE TYPE http_action_enum AS ENUM ('GET', 'HEAD', 'POST', 'PUT', 'DELETE', 'CONNECT', 'OPTIONS', 'TRACE', 'PATCH');
CREATE TABLE IF NOT EXISTS response
(
    id                          UUID                PRIMARY KEY,
    http_action                 http_action_enum    NOT NULL
);

但是当我使用 ef 框架插入 postgres 数据库时，我不断遇到以下错误：

Exception data:
Severity: ERROR
SqlState: 42804
MessageText: column "destination" is of type source_dest_enum but expression is of type integer
Hint: You will need to rewrite or cast the expression.

当我检查响应数据类型时，它实际上是正确的枚举而不是整数。

存储库.cs

public async Task<Response> InsertRecord(Response response, CancellationToken cancellationToken)
{
      await dBContext.response.AddAsync(response, cancellationToken).ConfigureAwait(true);
      await dBContext.SaveChangesAsync(cancellationToken).ConfigureAwait(true);

      return response;
}

DBContext.cs

      protected override void OnModelCreating(ModelBuilder modelBuilder)
      {
            modelBuilder.HasDefaultSchema("public");
            modelBuilder.HasPostgresEnum<SourceDestinationEnum>();
            modelBuilder.HasPostgresEnum<HttpActionEnum>();

            modelBuilder.Entity<Response>().Property(d => d.RespondedData).HasColumnType("json");

HttpActionEnum.cs

[JsonConverter(typeof(StringEnumConverter))]
    public enum HttpActionEnum
    {
        GET,
        POST,
    }

有人遇到过将 c# 枚举映射到 postgres 枚举并可以提供建议吗？

我尝试转换为枚举，但失败并出现错误，指出列的类型为枚举，但表达式的类型为文本。

https://learn.microsoft.com/en-us/ef/core/modeling/value-conversions

DBContext.cs（已更新）

      protected override void OnModelCreating(ModelBuilder modelBuilder)
      {
            modelBuilder.HasDefaultSchema("public");
            modelBuilder.HasPostgresEnum<SourceDestinationEnum>();
            modelBuilder.HasPostgresEnum<HttpActionEnum>();

           modelBuilder.Entity<Response>(entity =>
            {
                entity.Property(e => e.RespondedData).HasColumnType("json");
                entity.Property(e => e.Destination).HasConversion(
                    v => v.ToString(),
                    v => (SourceDestinationEnum)System.Enum.Parse(typeof(SourceDestinationEnum), v));
            });

错误

+       InnerException  {"42804: column \"destination\" is of type source_dest_enum but expression is of type text"}    System.Exception {Npgsql.PostgresException}

Answer 1

如果枚举只需要转换为字符串，类似这样的事情应该可以工作：

var converter = new EnumToStringConverter<HttpActionEnum>();

modelBuilder
    .Entity<Response>()
    .Property(e => e.RespondedData)
    .HasConversion(converter);