How to update the database after the datatable is modified

The data in the datatable can be modified and updated to the database at the same time, which is convenient. The following is the implementation code:

Datatable table = new datatable (); // initialize a datatable object string sqlconnectionstring = "Data Source = computername-PC; initial catalog = charge_sys; user id = sa; Pwd = 123456; "; sqlconnection = new sqlconnection (sqlconnectionstring); // connect to the database sqlcommand = new sqlcommand (" select * From testb ", sqlconnection); sqldataadapter sqladap = new sqldataadapter (sqlcommand ); sqlcommandbuilder sqlbuilder = new sqlcommandbuilder (sqladap); // This sentence is very important, as if it was used for batch update // dataset dtst = new dataset (); dataset can also be used for completion, the corresponding implementation code sqlconnection is as follows. open (); sqladap. fill (table); // table = dtst. tables ["testb"]; datarow DR = table. rows [0]; // The first line // dr. beginedit (); // dr. endedit (); it seems that the two statements are mainly used for (INT I = 0; I <table. rows. count; I ++) // modify the content of each row in the table {DR = table. rows [I]; Dr ["F"] = 3; // The field name is f} // a primary key must exist in the testb table, otherwise, it is very important that you cannot update/******* sqladap. update (table); // sqladap. update (dtst, "testb"); sqlconnection. close (); MessageBox. show ("AA ");

The following is the able bound to the datagridview control. When the data in the datagridview dview changes, update the database code:

Datatable and datagridview control binding code:

Private void form1_load (Object sender, eventargs e) {string sqlconnectionstring = "Data Source = computername-PC; initial catalog = charge_sys; user id = sa; Pwd = 123456 ;"; sqlconnection = new sqlconnection (sqlconnectionstring); // initialize sqlconnection datatable table = new datatable (); sqldataadapter sqladap = new sqldataadapter ("select * From testb", sqlconnection); sqlconnection. open (); sqladap. fill (table); sqlconnection. close (); // display the data in Table testb in the dview this. datagridview1.datasource = table ;}

Update the changes in the datagridview to the database code:

Private void butupdate_click (Object sender, eventargs e) {datatable table = new datatable (); table = (datatable) This. datagridview1.datasource; string sqlconnectionstring = "Data Source = wanghaitao-PC; initial catalog = charge_sys; user id = sa; Pwd = 123456;"; sqlconnection = new sqlconnection (sqlconnectionstring ); sqlcommand = new sqlcommand ("select * From testb", sqlconnection); sqldataadapter sqladap = new sqldataadapter (sqlcommand); sqlcommandbuilder sqlbuilder = new sqlcommandbuilder (sqladap); // sqlconnection is required. open (); sqladap. fill (table); // a primary key must exist in the testb table; otherwise, sqladap cannot be updated. update (table); sqlconnection. close (); MessageBox. show ("AA ");}