完善通用接口输入参数

visualdev/Tnb.Vengine/Domain/VmDbProp.cs

@@ -5,6 +5,7 @@
 
 using JNPF.Common.Extension;
 using Newtonsoft.Json;
+using NPOI.SS.Formula.Functions;
 using Yitter.IdGenerator;
 
 namespace Tnb.Vengine.Domain;
@@ -74,6 +75,15 @@ public class VmDbProp : VmBaseProp
 
     #endregion Properties
 
+    /// <summary>
+    /// 获取可空类型的字符串名称
+    /// </summary>
+    /// <returns></returns>
+    public string GetCsType()
+    {
+        return required ? csType : csType + "?";
+    }
+
     /// <summary>
     /// 获取默认值
     /// </summary>