Question

i have created a class and with that class i passed constructor and then i made that class abstract class, but when i want to get 1 attribute of the abstract class from the inherit class it showing some error can not take argument 0

public class Device1
{
    public int dwMachineNumber;
    public int dwBaudrate;
    public int dwCommPort;
    public string dwIPAddress;
    public int dwPort;
    public int dwPassWord;

    public Device1(int dwMachineNumber)
    {
        this.dwMachineNumber = dwMachineNumber;
    }

    public Device1(int dwMachineNumber, int dwBaudrate, int dwCommPort, string dwIPAddress, int dwPort, int dwPassWord)
    {
        this.dwMachineNumber = dwMachineNumber;
        this.dwBaudrate = dwBaudrate;
        this.dwCommPort = dwCommPort;
        this.dwIPAddress = dwIPAddress;
        this.dwPort = dwPort;
        this.dwPassWord = dwPassWord;
    }

}

public class EnableMachine : Device1
{
    public int Device_Busy; //if 0 busy and 1 not busy 

    public EnableMachine(int dwMachineNumber, int Device_Busy)
    {
        this.Device_Busy = Device_Busy;
        this.dwMachineNumber = dwMachineNumber;
    }
}

Answer 1

Try this:

public class EnableMachine : Device1
{
    public int Device_Busy; //if 0 busy and 1 not busy 

    public EnableMachine(int dwMachineNumber, int Device_Busy) 
        : base(dwMachineNumber)
    {
        this.Device_Busy = Device_Busy;
    }
}

EDIT:

When calling the constructor of a derived class, it also tries to call the constructor of the base class. Since you just had:

public EnableMachine(int dwMachineNumber, int Device_Busy)
{...}

it by default tries to call the parameterless constructor Device() but Device1 does not have a parameterless constructor; hence the error “..does not contain a method accepting 0 arguments”.

You need to tell it to use the constructor accepting the dwMachineNumber argument by adding the line

: base(dwMachineNumber)

to your derived class’s constructor. So, effectively, when you instantiate the derived class, it takes the dwMachineNumber argument and trunks it through to the base class’s constructor.