添加项目文件。

SamplePre.Models/Ext/sys_standard_ext.cs

@@ -0,0 +1,38 @@
+using Models.Models;
+using System;
+using System.Collections.Generic;
+using System.ComponentModel;
+using System.Linq;
+using System.Runtime.CompilerServices;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace SamplePre.Models.Ext
+{
+    public class sys_standard_ext : sys_standard ,INotifyPropertyChanged
+    {
+
+        //public bool IsSelected { get; set; }
+
+
+        private bool _isSelected;
+
+        public bool IsSelected
+        {
+            get { return _isSelected; }
+            set { _isSelected = value;
+
+                OnPropertyChanged();
+            }
+        }
+        protected void OnPropertyChanged([CallerMemberName] string? propertyName = null)
+        {
+            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
+        }
+
+        
+
+
+        public event PropertyChangedEventHandler? PropertyChanged;
+    }
+}