using System.ComponentModel.DataAnnotations;
namespace CampusErrand.Models;
///
/// 系统消息表
///
public class SystemMessage
{
[Key]
public int Id { get; set; }
/// 标题
[MaxLength(128)]
public string Title { get; set; } = string.Empty;
/// 正文(富文本)
public string Content { get; set; } = string.Empty;
/// 缩略图
[MaxLength(512)]
public string? ThumbnailUrl { get; set; }
/// 目标类型
public MessageTargetType TargetType { get; set; }
/// 指定用户 ID 列表(JSON)
public string? TargetUserIds { get; set; }
/// 发布时间
public DateTime CreatedAt { get; set; } = DateTime.UtcNow;
}