Reprinted csdn (educast): C # merge the two datatables with the same structure

Datatable DB = NULL;
Datatable dt = Ds. Tables [0];
//// Merge two data tables
DB = DT. Copy ();
Datarow [] foundrows = DT. Select ();
For (INT I = 0; I <foundrows. length; I ++)
{
DB. importrow (foundrows [I]);
}

1. // Merge DT with the same structure
2. Datatable ableable1 = new datatable ();
3. Datatable ableable2 = new datatable ();
4. Datatable newdatatable = datatable1.clone ();
6. Object [] OBJ = new object [newdatatable. Columns. Count];
7. For (INT I = 0; I <ableable1.rows. Count; I ++)
8. {
9. Datatable1.rows [I]. itemarray. copyto (OBJ, 0 );
10. Newdatatable. Rows. Add (OBJ );
11. }
13. For (INT I = 0; I <ableable2.rows. Count; I ++)
14. {
15. Datatable2.rows [I]. itemarray. copyto (OBJ, 0 );
16. Newdatatable. Rows. Add (OBJ );
17. }
18. // Merge DT with different structures
19. /// <Summary>
20. /// Combine two different able columns into a new datatable
21. /// </Summary>
22. /// <Param name = "dt1"> Table 1 </param>
23. /// <Param name = "dt2"> Table 2 </param>
24. /// <Param name = "dtname"> name of the merged table </param>
25. /// <Returns> </returns>
26. Private datatable unitedatatable (datatable dt1, datatable dt2, string dtname)
27. {
28. Datatable dt3 = dt1.clone ();
29. For (INT I = 0; I <dt2.columns. Count; I ++)
30. {
31. Dt3.columns. Add (dt2.columns [I]. columnname );
32. }
33. Object [] OBJ = new object [dt3.columns. Count];
35. For (INT I = 0; I <dt1.rows. Count; I ++)
36. {
37. Dt1.rows [I]. itemarray. copyto (OBJ, 0 );
38. Dt3.rows. Add (OBJ );
39. }
41. If (dt1.rows. Count> = dt2.rows. Count)
42. {
43. For (INT I = 0; I <dt2.rows. Count; I ++)
44. {
45. For (Int J = 0; j <dt2.columns. Count; j ++)
46. {
47. Dt3.rows [I] [J + dt1.columns. Count] = dt2.rows [I] [J]. tostring ();
48. }
49. }
50. }
51. Else
52. {
53. Datarow dr3;
54. For (INT I = 0; I <dt2.rows. Count-dt1.rows. Count; I ++)
55. {
56. Dr3 = dt3.newrow ();
57. Dt3.rows. Add (dr3 );
58. }
59. For (INT I = 0; I <dt2.rows. Count; I ++)
60. {
61. For (Int J = 0; j <dt2.columns. Count; j ++)
62. {
63. Dt3.rows [I] [J + dt1.columns. Count] = dt2.rows [I] [J]. tostring ();
64. }
65. }
66. }
67. Dt3.tablename = dtname; // sets the DT name.
68. Return dt3;
69. }
72. // Merge multiple data tables with the same structure
74. Public datatable getallentrysdatatable ()
75. {
76. Datatable newdatatable = getentrysdatatable (0). Clone ();
78. Object [] OBJ = new object [newdatatable. Columns. Count];
80. For (INT I = 0; I <entrygroups. getentrygroupcount (); I ++)
81. {
82. For (Int J = 0; j <getentrysdatatable (I). Rows. Count; j ++)
83. {
84. Getentrysdatatable (I). Rows [J]. itemarray. copyto (OBJ, 0 );
85. Newdatatable. Rows. Add (OBJ );
86. }
87. }
88. Return newdatatable;
89. }