添加项目文件。

Szmedi.RvKits/Attributes/GreaterThanAttribute.cs

@@ -0,0 +1,24 @@
+using System;
+using System.ComponentModel.DataAnnotations;
+
+namespace Szmedi.RvKits.Attributes
+{
+    public class GreaterThanAttribute : ValidationAttribute
+    {
+        public GreaterThanAttribute(string propertyName)
+        {
+            PropertyName = propertyName;
+        }
+
+        public string PropertyName { get; }
+
+        protected override ValidationResult IsValid(object value, ValidationContext validationContext)
+        {
+            object
+                instance = validationContext.ObjectInstance,
+                otherValue = instance.GetType().GetProperty(PropertyName).GetValue(instance);
+
+            return ((IComparable)value).CompareTo(otherValue) > 0 ? ValidationResult.Success : new("当前值小于另一个值");
+        }
+    }
+}