Compare new and old data in a able

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1/** // <summary>
2 // compare two data tables and return the comparison result table
3 // comparison conditions:
4 // 1. The two tables have the same structure;
5 // 2. Both tables are sorted by the primary key order;
6 // 3. Both tables are not empty;
7 /// </summary>
8 /// <param name = "newTable"> new data </param>
9 /// <param name = "oldTable"> old data </param>
10 /// <param name = "parmaryKey"> table primary key name </param>
11 /// <param name = "colState"> name of the Status column </param>
12 /// <param name = "stateValue"> Status values of different States </param>
13 /// <returns> result table </returns>
14 public static DataTable CompareData (
15 this DataTable newTable,
16 DataTable oldTable,
17 string parmaryKey,
18 string colState,
19 object stateValue)
20 {
21 int newTableCount = newTable. Rows. Count;
22 int oldTableCount = oldTable. Rows. Count;
23
24/** // compare the result table
25 DataTable resultTable = newTable. Clone ();
26
27 int I = 0, j = 0;
28 do
29 {
30 DataRow dr1 = null;
31 DataRow dr2 = null;
32
33/** // result line
34 DataRow rDr = resultTable. NewRow ();
35
36/*** // if the number of columns in the old table exceeds the limit, add all other columns in the new table.
37 if (j <oldTableCount)
38 {
39 dr2 = oldTable. Rows [j];
40}
41 else
42 {
43 for (int k = I; k <newTableCount; k ++)
44 {
45 DataRow rDr2 = resultTable. NewRow ();
46 rDr2.ItemArray = newTable. Rows [k]. ItemArray;
47 resultTable. Rows. Add (rDr2 );
48}
49/** // exit after adding
50 break;
51}
52
53/** // if the new table is exceeded, set the status value for the remaining data of the old table and add it to the result table.
54 if (I <newTableCount)
55 {
56 dr1 = newTable. Rows [I];
57}
58 else
59 {
60 for (int k = j; k <oldTableCount; k ++)
61 {
62 DataRow rDr2 = resultTable. NewRow ();
63 rDr2.ItemArray = oldTable. Rows [k]. ItemArray;
64 rDr2 [colState] = stateValue;
65 resultTable. Rows. Add (rDr2 );
66}
67/** // exit after adding
68 & nbs