[原创]创建指定RowState属性的DataRow实例

 

 1private void button1_Click(object sender, RoutedEventArgs e)
 2        {
 3            MessageBox.Show(CreateStateRow<cinlapdemoDataSet.CustomersDataTable,cinlapdemoDataSet.CustomersRow>().RowState.ToString());
 4        }
 5
 6        public static R CreateStateRow<T, R>(params NewRowState[] newRowState)
 7            where T : DataTable
 8            where R : DataRow
 9        {
10            NewRowState nrs = NewRowState.Modified;
11
12            if (newRowState.Length > 1)
13            {
14                throw new Exception("创建行状态个数大于1");
15            }
16            else if (newRowState.Length == 1)
17            {
18                nrs = newRowState[0];
19            }
20
21            int oldRecord = 1;
22            int newRecord = 2;
23
24            if (nrs != NewRowState.Modified)
25            {
26                if (nrs == NewRowState.Added)
27                {
28                    oldRecord = -1;
29                    newRecord = 1;
30                }
31                else
32                {
33                    oldRecord = 1;
34                    newRecord = -1;
35                }
36            }
37
38            Type tableType = typeof(T);
39            Type rowType = typeof(R);
40
41            T dataTable = (T)tableType.Assembly.CreateInstance(tableType.FullName);
42
43            DataRow row = dataTable.NewRow();
44
45            FieldInfo fiOldRecord = rowType.GetField("oldRecord", BindingFlags.NonPublic | BindingFlags.Instance);
46            FieldInfo fiNewRecord = rowType.GetField("newRecord", BindingFlags.NonPublic | BindingFlags.Instance);
47
48            fiOldRecord.SetValue(row, oldRecord);
49            fiNewRecord.SetValue(row, newRecord);
50
51            return (R)row;
52        }
53
54        public enum NewRowState : int
55        {
56            Added = 0,
57            Modified = 1,
58            Deleted = 2
59        }