Using examples to illustrate how to use C # to extract data from the database and generate custom Excel tables as required?

/* Extract data from the database */
String strconn = "packet size = 4096; user id = sa; Data Source = localhost; persist Security info = true; initial catalog = database; Password = sa ";
Sqlconnection sqlconn = new sqlconnection (strconn );
Sqlconn. open ();
Sqldataadapter = new sqldataadapter ("select * from [data table]", sqlconn );
Dataset myds = new dataset ();
Sqldataadapter. Fill (myds );
/* Create a "result table" format table in execl */
Excel. applicationclass Excel = new excel. applicationclass ();
Excel. application. workbooks. Add (true );
Excel. cells [1, 1] = "unit name ";
Excel. cells [] = "indicators and their descriptions, feature values and weights ";
Excel. cells [] = "properties ";
Excel. cells [2, 2] = "D ";
Excel. cells [2, 5] = "R ";
Excel. cells [2, 8] = "";
Excel. cells [2, 11] = "S ";
Excel. cells [2, 14] = "T ";
Excel. cells [2, 17] = "I ";
Excel. cells [2, 20] = "C ";
Excel. cells [2, 23] = "result ";
Excel. cells [2, 24] = "Grade ";
Excel. cells [3, 2] = "Description ";
Excel. cells [3, 3] = "feature value ";
Excel. cells [3, 4] = "weight ";
Excel. cells [3, 5] = "Description ";
Excel. cells [3, 6] = "feature value ";
Excel. cells [3, 7] = "weight ";
Excel. cells [3, 8] = "Description ";
Excel. cells [3, 9] = "feature value ";
Excel. cells [3, 10] = "weight ";
Excel. cells [3, 11] = "Description ";
Excel. cells [3, 12] = "feature value ";
Excel. cells [3, 13] = "weight ";
Excel. cells [3, 14] = "Description ";
Excel. cells [3, 15] = "feature value ";
Excel. cells [3, 16] = "weight ";
Excel. cells [3, 17] = "Description ";
Excel. cells [3, 18] = "feature value ";
Excel. cells [3, 19] = "weight ";
Excel. cells [3, 20] = "Description ";
Excel. cells [3, 21] = "feature value ";
Excel. cells [3, 22] = "weight ";

Excel. get_range (Excel. cells [1, 1], Excel. cells [3, 1]). mergecells = true;
Excel. get_range (Excel. cells [1, 2], Excel. cells [1, 22]). mergecells = true;
Excel. get_range (Excel. cells [1, 23], Excel. cells [1, 24]). mergecells = true;
Excel. get_range (Excel. cells [2, 2], Excel. cells [2, 4]). mergecells = true;
Excel. get_range (Excel. cells [2, 5], Excel. cells [2, 7]). mergecells = true;
Excel. get_range (Excel. cells [2, 8], Excel. cells [2, 10]). mergecells = true;
Excel. get_range (Excel. cells [2, 11], Excel. cells [2, 13]). mergecells = true;
Excel. get_range (Excel. cells [2, 14], Excel. cells [2, 16]). mergecells = true;
Excel. get_range (Excel. cells [2, 17], Excel. cells [2, 19]). mergecells = true;
Excel. get_range (Excel. cells [2, 20], Excel. cells [2, 22]). mergecells = true;
Excel. get_range (Excel. cells [2, 23], Excel. cells [3, 23]). mergecells = true;
Excel. get_range (Excel. cells [2, 24], Excel. cells [3, 24]). mergecells = true;

/* Write data to an Excel format table */
Int waterdatarows = myds. Tables [0]. Rows. count;
Int waterdatacols = myds. Tables [0]. Columns. count;
For (INT I = 1; I <= waterdatarows; I ++)
{
Excel. cells [I + 3, 1] = myds. Tables [0]. Rows [I-1]. itemarray. getvalue (0 );
For (Int J = 1; j <= 7; j ++)
{
Excel. cells [I + 3, 3 * j] = myds. Tables [0]. Rows [I-1]. itemarray. getvalue (j );
Excel. cells [I + 3, 3 * j + 1] = WW [J-1];
}
Excel. cells [I +] = Ds. Tables [0]. Rows [I-1]. itemarray. getvalue (1 );
Excel. cells [I +] = Ds. Tables [0]. Rows [I-1]. itemarray. getvalue (3 );
}
Excel. Visible = false;
Excel. displayalerts = false;
// Excel. worksheetclass worksheet = (Excel. worksheetclass) excel. activesheet;
Excel. Save ();
Excel. application. workbooks. Close ();
Excel. application. Quit ();
Excel. Quit ();
System. runtime. interopservices. Marshal. releasecomobject (Excel );
Killprocess ("Excel. EXE ");
GC. Collect ();