I have {get; set;} methods for all my properties, but I keep getting an error of "A get or set accessor expected"

Question

Sorry if this seems dumb, but I've looked through other questions regarding this issue and I can't find anything. I'm transitioning from Java to C#, so I'm probably missing something to do with properties that I would have just done using methods in Java.

In Monodevelop, I keep getting

A get or set accessor expected

as an error when I compile.

Here's my code.

Program.cs:

class MainClass
{
    public static void Main (string[] args)
    {
        Transaction myTransaction = new Transaction ();
        string[] data = Console.ReadLine ().Split(',');
        while (data[0] != "#") {
            myTransaction.Name = data [0];
            Double.TryParse (data [1], out myTransaction.Cost);
            Int32.TryParse (data [2], out myTransaction.Quantity);
            Console.WriteLine (Transaction);
            data = Console.ReadLine ().Split(',');
        }
    }
}
}

Transaction Class:

using System;


public class Transaction
{
    //private vars//
    //string name;
    //double cost;
    //int quantity;

    //Constructor//
    public Transaction ()
    {

    }

    //Properties//
    public string Name{ get; set;}
    public double Cost{ get; set;}
    public int Quantity{ get; set;}

    //methods//
    public double CalcTotal(){
        return Quantity * Cost;
    }

    public override String ToString{
        return String.format("{0:0.00} x {1:0.00} @ ${2:0.00} Total: ${3:0.00}", Name, Quantity, Cost, CalcTotal()); 


    }
}
}

Answer 1

There are several problems with your code:

1. Your ToString method is lacking its parenthesis, the return statement inside is likely the one giving you the error you refer to in your question
2. String.Format is written with a lowercase f, String.format, which won't compile.
3. You cannot use ref or out parameters and target properties, you must target variables, like local variables or fields.
4. Console.WriteLine(Transaction) cannot write the class, it must write an object, so you likely want to use Console.WriteLine(myTransaction);.

Answer 2

The problem is in your ToString method, you forgot ()

public override string ToString () {            
    return string.Format("{0:0.00} x {1:0.00} @ ${2:0.00} Total: ${3:0.00}", Name, Quantity, Cost, CalcTotal());                
}

Also you have couple more problems:

Console.WriteLine(Transaction); 

should be

Console.WriteLine(myTransaction);

And properties can't be ref and out parameters

See working fiddle

Answer 3

In your code you are passing a property of the class as a ref and out. You can't do this, because C# can't know is there a backend field behind the Property.Why ??? You can simply have this property like

public double Cost
{ 
   get { return 4.5; } 
   set { /* empty */ }
}

And here what will do CLR with your out and ref parameters?It can't set any value to the property.

 Double.TryParse (data [1], out myTransaction.Cost);
 Int32.TryParse (data [2], out myTransaction.Quantity);

And here you need

Console.WriteLine (myTransaction);

not

Console.WriteLine (Transaction);

and the ToString() must be

public override string ToString(){
     return String.format("{0:0.00} x {1:0.00} @ ${2:0.00} Total: ${3:0.00}", Name, Quantity, Cost, CalcTotal());     
}

Answer 4

The issue you are having is with (I am assuming) is with your parse statements. You cann't pass an out or ref as a property or indexer of a class.

Transaction myTransaction = new Transaction();
string[] data = Console.ReadLine().Split(',');
while (data[0] != "#")
{
    myTransaction.Name = data[0];
    Double.TryParse(data[1], out myTransaction.Cost); //<-- this is the issue
    Int32.TryParse(data[2], out myTransaction.Quantity); //<-- here again
    Console.WriteLine(myTransaction);
    data = Console.ReadLine().Split(',');
}

What you will need to do is hold the value in a seperate variable and then assign it to the Transaction object as.

Transaction myTransaction = new Transaction();
string[] data = Console.ReadLine().Split(',');
while (data[0] != "#")
{
    myTransaction.Name = data[0];

    double dCost;
    int dQty;

    Double.TryParse(data[1], out dCost); //<-- this is hte issue
    Int32.TryParse(data[2], out dQty); //<-- here again
    myTransaction.Cost = dCost;
    myTransaction.Quantity = dQty;
    Console.WriteLine(myTransaction);
    data = Console.ReadLine().Split(',');
}

So as you see we have created two additional variables in the loop dCost & dQty during the loop the values are parsed to the local variables, then these variables are set to the instance of the Transaction myTransaction.

In addition there are two other small issues with the code.

1. The override ToString should be a method as ToString()
2. The method string.format(..) is actually string.Format()

Finally as others pointed out Console.WriteLine(Transaction); should be Console.WriteLine(myTransaction);