带列显示/隐藏popup的DatagridView（控制显示哪些列）Demo+源码

<?xml version="1.0" standalone="yes"?> <DocumentElement> <category> <CustomerID>ALFKI</CustomerID> <CompanyName>Alfreds Futterkiste</CompanyName> <City>Berlin</City> <Country>Germany</Country> <Orders>200</Orders> <PeakDate>5/2/2006</PeakDate> </category> <category> <CustomerID>ANATR</CustomerID> <CompanyName>Ana Trujillo Emparedados y helados</CompanyName> <City>Mxico D.F.</City> <Country>Mexico</Country> <Orders>200</Orders> <PeakDate>5/2/2006</PeakDate> </category> <category> <CustomerID>ANTON</CustomerID> <CompanyName>Antonio Moreno Taquera</CompanyName> <City>Mxico D.F.</City> <Country>Mexico</Country> <Orders>400</Orders> <PeakDate>6/2/2006</PeakDate> </category> <category> <CustomerID>AROUT</CustomerID> <CompanyName>Around the Horn</CompanyName> <City>London</City> <Country>UK</Country> <Orders>400</Orders> <PeakDate>6/2/2006</PeakDate> </category> <category> <CustomerID>BERGS</CustomerID> <CompanyName>Berglunds snabbkp</CompanyName> <City>Lule</City> <Country>Sweden</Country> <Orders>400</Orders> <PeakDate>6/2/2006</PeakDate> </category> <category> <CustomerID>BLAUS</CustomerID> <CompanyName>Blauer See Delikatessen</CompanyName> <City>Mannheim</City> <Country>Germany</Country> <Orders>400</Orders> <PeakDate>6/2/2006</PeakDate> </category> <category> <CustomerID>BLONP</CustomerID> <CompanyName>Blondesddsl pre et fils</CompanyName> <City>Strasbourg</City> <Country>France</Country> <Orders>400</Orders> <PeakDate>6/2/2006</PeakDate> </category> <category> <CustomerID>BOLID</CustomerID> <CompanyName>Blido Comidas preparadas</CompanyName> <City>Madrid</City> <Country>Spain</Country> <Orders>400</Orders> <PeakDate>6/2/2006</PeakDate> </category> <category> <CustomerID>BONAP</CustomerID> <CompanyName>Bon app'</CompanyName> <City>Marseille</City> <Country>France</Country> <Orders>600</Orders> <PeakDate>6/2/2006</PeakDate> </category> <category> <CustomerID>BOTTM</CustomerID> <CompanyName>Bottom-Dollar Markets</CompanyName> <City>Tsawassen</City> <Country>Canada</Country> <Orders>500</Orders> <PeakDate>6/2/2006</PeakDate> </category> <category> <CustomerID>BSBEV</CustomerID> <CompanyName>B's Beverages</CompanyName> <City>London</City> <Country>UK</Country> <Orders>500</Orders> <PeakDate>6/2/2006</PeakDate> </category> <category> <CustomerID>CACTU</CustomerID> <CompanyName>Cactus Comidas para llevar</CompanyName> <City>Buenos Aires</City> <Country>Argentina</Country> <Orders>500</Orders> <PeakDate>6/2/2006</PeakDate> </category> <category> <CustomerID>CHOPS</CustomerID> <CompanyName>Chop-suey Chinese</CompanyName> <City>Bern</City> <Country>Switzerland</Country> <Orders>200</Orders> <PeakDate>6/2/2006</PeakDate> </category> <category> <CustomerID>COMMI</CustomerID> <CompanyName>Comrcio Mineiro</CompanyName> <City>Sao Paulo</City> <Country>Brazil</Country> <Orders>200</Orders> <PeakDate>6/2/2006</PeakDate> </category> <category> <CustomerID>CONSH</CustomerID> <CompanyName>Consolidated Holdings</CompanyName> <City>London</City> <Country>UK</Country> <Orders>200</Orders> <PeakDate>6/2/2006</PeakDate> </category> <category> <CustomerID>DRACD</CustomerID> <CompanyName>Drachenblut Delikatessen</CompanyName> <City>Aachen</City> <Country>Germany</Country> <Orders>200</Orders> <PeakDate>6/2/2006</PeakDate> </category> <category> <CustomerID>DUMON</CustomerID> <CompanyName>Du monde entier</CompanyName> <City>Nantes</City> <Country>France</Country> <Orders>300</Orders> <PeakDate>6/2/2006</PeakDate> </category> <category> <CustomerID>EASTC</CustomerID> <CompanyName>Eastern Connection</CompanyName> <City>London</City> <Country>UK</Country> <Orders>400</Orders> <PeakDate>6/2/2006</PeakDate> </category> <category> <CustomerID>ERNSH</CustomerID> <CompanyName>Ernst Handel</CompanyName> <City>Graz</City> <Country>Austria</Country> <Orders>400</Orders> <PeakDate>6/2/2006</PeakDate> </category> <category> <CustomerID>FAMIA</CustomerID> <CompanyName>Familia Arquibaldo</CompanyName> <City>Sao Paulo</City> <Country>Brazil</Country> <Orders>400</Orders> <PeakDate>6/2/2006</PeakDate> </category> <category> <CustomerID>FOLIG</CustomerID> <CompanyName>Folies gourmandes</CompanyName> <City>Lille</City> <Country>France</Country> <Orders>400</Orders> <PeakDate>6/2/2006</PeakDate> </category> <category> <CustomerID>FOLKO</CustomerID> <CompanyName>Folk och f HB</CompanyName> <City>Brcke</City> <Country>Sweden</Country> <Orders>400</Orders> <PeakDate>6/1/2006</PeakDate> </category> <category> <CustomerID>FRANK</CustomerID> <CompanyName>Frankenversand</CompanyName> <City>Mnchen</City> <Country>Germany</Country> <Orders>400</Orders> <PeakDate>6/1/2006</PeakDate> </category> <category> <CustomerID>FRANR</CustomerID> <CompanyName>France restauration</CompanyName> <City>Nantes</City> <Country>France</Country> <Orders>400</Orders> <PeakDate>6/1/2006</PeakDate> </category> <category> <CustomerID>FRANS</CustomerID> <CompanyName>Franchi S.p.A.</CompanyName> <City>Torino</City> <Country>Italy</Country> <Orders>300</Orders> <PeakDate>6/1/2006</PeakDate> </category> <category> <CustomerID>FURIB</CustomerID> <CompanyName>Furia Bacalhau e Frutos do Mar</CompanyName> <City>Lisboa</City> <Country>Portugal</Country> <Orders>300</Orders> <PeakDate>6/1/2006</PeakDate> </category> <category> <CustomerID>GALED</CustomerID> <CompanyName>Galera del gastrnomo</CompanyName> <City>Barcelona</City> <Country>Spain</Country> <Orders>600</Orders> <PeakDate>6/1/2006</PeakDate> </category> <category> <CustomerID>GODOS</CustomerID> <CompanyName>Godos Cocina Tpica</CompanyName> <City>Sevilla</City> <Country>Spain</Country> <Orders>200</Orders> <PeakDate>6/1/2006</PeakDate> </category> <category> <CustomerID>GOURL</CustomerID> <CompanyName>Gourmet Lanchonetes</CompanyName> <City>Campinas</City> <Country>Brazil</Country> <Orders>200</Orders> <PeakDate>6/1/2006</PeakDate> </category> <category> <CustomerID>GREAL</CustomerID> <CompanyName>Great Lakes Food Market</CompanyName> <City>Eugene</City> <Country>USA</Country> <Orders>200</Orders> <PeakDate>6/1/2006</PeakDate> </category> <category> <CustomerID>GROSR</CustomerID> <CompanyName>GROSELLA-Restaurante</CompanyName> <City>Caracas</City> <Country>Venezuela</Country> <Orders>200</Orders> <PeakDate>6/1/2006</PeakDate> </category> <category> <CustomerID>HANAR</CustomerID> <CompanyName>Hanari Carnes</CompanyName> <City>Rio de Janeiro</City> <Country>Brazil</Country> <Orders>200</Orders> <PeakDate>6/1/2006</PeakDate> </category> <category> <CustomerID>HILAA</CustomerID> <CompanyName>HILARION-Abastos</CompanyName> <City>San Cristbal</City> <Country>Venezuela</Country> <Orders>200</Orders> <PeakDate>6/1/2006</PeakDate> </category> <category> <CustomerID>HUNGC</CustomerID> <CompanyName>Hungry Coyote Import Store</CompanyName> <City>Elgin</City> <Country>USA</Country> <Orders>200</Order