Merge multiple row headers in the gridview

Multiple row headers are merged and there are many instances on the Internet. The details are detailed here, so that everyone can understand them.
Implementation principle: display the table header of the HMTL table in ASP. NET.
When creating a Row Header Row in the GridView: e. Row. RowType = DatacontrolRowType. Header
Clear the old header, and then splice the new header.

TableHeaderCell thc = new TableHeaderCell ();

Thc. Text = "Header ";

The generated HTML is: <th> header </th>

Merge multiple row headers

Test multi-row merge Header
Header	Header 1	Header 2		Header 3
	Header 1-1	Header 2-1	Header 2-2	Header 3-1	Header 3-2	Header 3-3

1 protected void gridview1_rowcreated (Object sender, gridviewroweventargs E)
2 {
3 // determine whether the created row is a header row
4 If (E. Row. rowtype = datacontrolrowtype. header)
5 {
6 // obtain all cells in the row where the header is located
7 tablecellcollection tcheader = E. Row. cells;
8 // clear automatically generated Headers
9 tcheader. Clear ();
10
11 // the newly added first header cell is set to merge seven columns to form a row.
12 tcheader. Add (New tableheadercell ());
13 tcheader [0]. columnspan = 7;
14 tcheader [0]. Text = "test multi-row merge header </Th> </tr> <tr> ";
15 // </Th> indicates that the current cell ends, </tr> indicates that the row ends, and <tr> starts a new key line.
16
17 // Add the second header cell and set it to merge the two rows.
18 tcheader. Add (New tableheadercell ());
19 tcheader [1]. rowspan = 2;
20 tcheader [1]. Text = "Header ";
21
22 tcheader. Add (New tableheadercell ());
23 tcheader [2]. Text = "header 1 ";
24
25 tcheader. Add (New tableheadercell ());
26 tcheader [3]. columnspan = 2;
27 tcHeader [3]. Text = "header 2 ";
28
29 tcHeader. Add (new TableHeaderCell ());
30 tcHeader [4]. ColumnSpan = 3;
31 tcHeader [4]. Text = "header 3 </th> </tr> <tr> ";
32
33 // all cells in the second row are added, with a line break </th> </tr> <tr>
34
35 // Add all cells in the third row
36 tcHeader. Add (new TableHeaderCell ());
37 tcHeader [5]. Text = "header 1-1 ";
38
39 tcHeader. Add (new TableHeaderCell ());
40 tcHeader [6]. Text = "header 2-1 ";
41
42 tcHeader. Add (new TableHeaderCell ());
43 tcHeader [7]. Text = "header 2-2 ";
44
45 tcHeader. Add (new TableHeaderCell ());
46 tcHeader [8]. Text = "header 3-1 ";
47
48 tcHeader. Add (new TableHeaderCell ());
49 tcHeader [9]. Text = "header 3-2 ";
50
51 tcHeader. Add (new TableHeaderCell ());
52 tcHeader [10]. Text = "header 3-3 </th> </tr> <tr> ";
53}
54
55}