here is an example,
public string a_UId, a_ProgramID, a_BuildingID, a_UserName, a_Level;
public long b_Linetype= 0, b_TotalLine = 0;
here is an example,
public string a_UId, a_ProgramID, a_BuildingID, a_UserName, a_Level;
public long b_Linetype= 0, b_TotalLine = 0;
You're not "declaring a string with more than one value". You're declaring several different variables. It's really important to differentiate between variables and values.
So:
public string x, y, z;
is equivalent to:
public string x;
public string y;
public string z;
(As an aside, I'd strongly advise you to ditch the prefixes, and make all fields private.)