database - Using OleDb.OleDb??? vb code ExecuteReader: Connection property has not been initialized -

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i trying load datagridview call dgvinfo information database. quite new vb , don't understand problem lies in code @ moment.

private sub frmproductinformation_load(byval sender system.object, byval e system.eventargs) handles mybase.load     dim conn new oledb.oledbconnection     dim dt new datatable     dim cmd new oledb.oledbcommand()     dim readit oledb.oledbdatareader     conn.connectionstring = "provider=microsoft.ace.oledb.12.0;data source=n:\data\gamehq.accdb"     conn.open()     readit = cmd.executereader()     readit.read()     dt.load(readit)     dgvinfo.datasource = dt     dgvinfo.refresh()     conn.close() end sub

this code , hope able point out if i've missed something.

you have initialize cmd. assuming don't use transactions, put query , connection cmd. btw - didn't specify sql query yet:

dim conn new oledb.oledbconnection dim dt new datatable dim readit oledb.oledbdatareader conn.connectionstring = "provider=microsoft.ace.oledb.12.0;data source=n:\data\gamehq.accdb" conn.open() dim cmd new oledb.oledbcommand("select * <whatever select from>", conn) readit = cmd.executereader() readit.read() dt.load(readit) dgvinfo.datasource = dt dgvinfo.refresh() conn.close()

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