Type conversion error

[nithya176]

Hey guys..i jus thought if u cud help me out wit this error im gettin.
Im writing a c# code to create an add-in in visio using VSTO.
I found this code which was in VB and i'm tryin to convert it to c# :

VB
Dim commandBars As Office.CommandB ars
Dim commandBar As Office.CommandB ar

commandBars = Application.Com mandBars
commandBar = commandBars.Add ("Demo Toolbar", _
Office.MsoBarPo sition.msoBarTo p, , True)
' Set the context when the toolbar is visible.
commandBar.Cont ext = Visio.VisUIObjS ets.visUIObjSet Drawing & "*"

' Add a button with a smiley face icon.
DemoButton = _
commandBar.Cont rols.Add(Office .MsoControlType .msoControlButt on)
DemoButton.Tag = "Demo Button"
DemoButton.Face Id = 2950
DemoButton.Tool tipText = "Run Demo"

c#
private void ThisAddIn_Start up(object sender, System.EventArg s e)
1 {
2 Microsoft.Offic e.Core.CommandB ars commandBars;
3 Microsoft.Offic e.Core.CommandB ar commandBar;

4 commandBars = Application.Com mandBars;
5 commandBar = commandBars.Add ("Demo Toolbar",Office .MsoBarPosition .msoBarTop,"",t rue);
//set the context menu when the toolbar is visible.
6 commandBar.Cont ext = Visio.VisUIObjS ets.visUIObjSet Drawing & "*";

//add a button wth a smiley face icon

7 Microsoft.Offic e.Core.CommandB arButton DemoButton = (Microsoft.Offi ce.Core.Command BarButton)comma ndBar.Controls. Add(Office.MsoC ontrolType.msoC ontrolButton,"" ,"","","");
8 DemoButton.Tag = "Demo Button";
9 DemoButton.Face Id = 2950;
10 DemoButton.Tool tipText= "Run Demo";



}

the error i'm gettin:

line 4: :Cannot implicitly convert type 'bject' to 'Microsoft.Offi ce.Core.Command Bars'. An explicit conversion exists(you are missing a cast?)

line 6: Operator '&' cannot be applied to operands of type 'Microsoft.Offi ce.Interop.Visi o.VisUIObjects' and 'string'

Plz help me out wit this error. Thanks in advance