sql - How to extract data from Access db and place it into a text box using vb.net? -

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hi guys i'm trying search employee information using sql ms access, , hoping put fname lname , such details in respective textbox correspond specific employee's id number. have managed make sql work don't know how extract files sql statement , place inside .text(text box), can please guide me? thanks

here code far: (updated code) got error message : additional information: executereader: connection property has not been initialized. highlighting reader below. how can fix this? i'm trying extract data , place textbox? thanks

private sub enumtext_selectedindexchanged(sender object, e eventargs) handles enumtext.selectedindexchanged           dim dbsource = "data source= c:\databse\company_db.accdb"         con.connectionstring = "provider=microsoft.ace.oledb.12.0; data source= c:\databse\company_db.accdb"          dim sqlquery string         dim sqlcommand new oledbcommand         dim sqladapter new oledbdataadapter         dim table new datatable          dim empnum string         dim empfname string         dim emplname string         dim empdept string         dim empstat string         dim empyears string          empnum = enumtext.text         empfname = empfnametext.text         emplname = emplnametext.text         empdept = depttext.text         empstat = stattext.text         empyears = yearstext.text          sqlquery = "select * tbl_empinfo empid empnum"          sqlcommand             .commandtext = sqlquery             .connection = con             .parameters.addwithvalue("empid", empnum)             sqladapter                 .selectcommand = sqlcommand                 .fill(table)             end             datagridview1                 .datasource = table             end         end          dim path = "data source= c:\databse\company_db.accdb"         dim command = "select * tbl_empinfo empid empnum"         querydata(path, command)           con.close()      end sub     private sub querydata(pathdb string, command string)         using connection new system.data.oledb.oledbconnection("provider=microsoft.ace.oledb.12.0;data source=" & pathdb)             using da new system.data.oledb.oledbcommand(command, connection)                 connection.open()                  dim reader = da.executereader()                 if reader.read()                     empfnametext.text = reader("fname")                     emplnametext.text = reader("lname")                 end if                  connection.close()             end using         end using     end sub

for this, need classes: connection, command, reader. other classes in code in question, redundant , required in complicated simple case presentation.

private sub querydata(pathdb string, command string)     using connection new system.data.oledb.oledbconnection("provider=microsoft.ace.oledb.12.0;data source=" & pathdb)         using com new system.data.oledb.oledbcommand(command, connection)             connection.open()              dim reader = com.executereader()             if reader.read()                 textbox1.text = reader("fname")                 textbox2.text = reader("lname")             end if              connection.close()         end using     end using end sub

call method so:

dim path = "c:\databse\company_db.accdb" dim command = "select * tbl_empinfo empid empnum" querydata(path, command)

edit - use parameters:

private sub querydata(pathdb string, command string, id string)     using connection new system.data.oledb.oledbconnection("provider=microsoft.ace.oledb.12.0;data source=" & pathdb)         using com new system.data.oledb.oledbcommand(command, connection)             com.parameters.addwithvalue("", id)              connection.open()              using reader = com.executereader()                 if reader.read()                     textbox1.text = reader("fname")                     textbox2.text = reader("lname")                 end if             end using              connection.close()         end using     end using end sub

call method:

dim path = "c:\databse\company_db.accdb" dim command = "select * tbl_empinfo empid = ?" dim empnum = "..." querydata(path, command, empnum)

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