添加项目文件。

Szmedi.RvKits/Attributes/MinimumAttribute.cs

@@ -0,0 +1,24 @@
+using System;
+using System.ComponentModel.DataAnnotations;
+using System.Linq;
+
+namespace Szmedi.RvKits.Attributes
+{
+    [AttributeUsage(AttributeTargets.Property | AttributeTargets.Field | AttributeTargets.Parameter)]
+    public class MinimumAttribute : ValidationAttribute
+    {
+        public MinimumAttribute(double minValue = 0)
+        {
+            MinValue = minValue;
+        }
+
+        public double MinValue { get; }
+
+        protected override ValidationResult IsValid(object value, ValidationContext validationContext)
+        {
+            return double.TryParse(value.ToString(), out double d) && d >= MinValue
+                ? ValidationResult.Success
+                : new ValidationResult("输入值超出范围");
+        }
+    }
+}