初步完成邮件功能

DMS.Core/Models/EmailTemplate.cs

@@ -0,0 +1,62 @@
+using System.ComponentModel.DataAnnotations;
+
+namespace DMS.Core.Models
+{
+    /// <summary>
+    /// 邮件模板实体
+    /// </summary>
+    public class EmailTemplate
+    {
+        /// <summary>
+        /// 模板ID
+        /// </summary>
+        public int Id { get; set; }
+
+        /// <summary>
+        /// 模板名称
+        /// </summary>
+        [Required]
+        [MaxLength(100)]
+        public string Name { get; set; }
+
+        /// <summary>
+        /// 模板代码（唯一标识）
+        /// </summary>
+        [Required]
+        [MaxLength(50)]
+        public string Code { get; set; }
+
+        /// <summary>
+        /// 模板主题
+        /// </summary>
+        [Required]
+        [MaxLength(500)]
+        public string Subject { get; set; }
+
+        /// <summary>
+        /// 模板内容
+        /// </summary>
+        [Required]
+        public string Body { get; set; }
+
+        /// <summary>
+        /// 是否为HTML格式
+        /// </summary>
+        public bool IsHtml { get; set; } = true;
+
+        /// <summary>
+        /// 是否启用
+        /// </summary>
+        public bool IsActive { get; set; } = true;
+
+        /// <summary>
+        /// 创建时间
+        /// </summary>
+        public DateTime CreatedAt { get; set; } = DateTime.Now;
+
+        /// <summary>
+        /// 更新时间
+        /// </summary>
+        public DateTime UpdatedAt { get; set; } = DateTime.Now;
+    }
+}