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Are private fields needed in a class where no methods exist?

I've been using ReSharper to do some work on cleaning up a C# codebase. I had been using both private fields in model classes along with public properties. However, I'm finding that I can simply take the properties that have no backing fields and convert them into auto-properties. These are model classes; no methods exist within them to impact the data in the objects. Is it better to just use the auto-properties?
EDIT: Including example of "Backing fields"
public class Gizmo
{
//this is what I call the "backing" field, only because it's "behind" the
//publicly-accessible property and you access it through the property
private Int32 _count;
//and this is the property, of course
public Int32 Count
{
get { return _count; }
set { _count = value; }
}
}

Is it better to just use the auto-properties
If your property involve is simple get;set, you can just use a "auto-property". If I am not wrong, compiler will create a private backing field behind the scenes.
If in your property, you are doing some kind of validation before; say before set then it makes sense to use a property with a backing field (non-auto)
An example would be
private string name;
public string MyName {
get {
return name;
}
set {
name = (value == null)
? "Anonymous" : value;
}
}

Methods are irrelevant here. If you have a property of:
private int foo;
public int Foo
{
get { return foo; }
set { foo = value; }
}
Then it absolutely makes sense to turn that into:
public int Foo { get; set; }
If any other code uses the private field, you can just change it to use the property instead.

This is pretty much a code-style question. So you should have a standard for model properties throughout your project or solution. If you find that the auto properties makes your intent more obvious, by all means use them--just use them consistently.

When to use get and set in C# class declaration [duplicate]

This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
Difference between Property and Field in C# .NET 3.5+
What's the difference between using
public string Username { get; set; }
and using
public string Username;
I have always been using the first one, but wanted to understand if there is any difference between the two, and scenarios when one should prefer over the other.

public string Username { get; set; }
is a Property.
while
public string Username;
is a Public variable.
For more comparison,
Reflection works differently on variables vs. properties, so if you rely on reflection, it's easier to use all properties.
You can't databind against a variable.
Changing a variable to a property is a breaking change.
Other link
Properties vs. Public Variables

One thing you can do with properties that you can't do with fields is limit visibility for either setter or getter:
public string MyProperty { get; private set; }
Something I use quite a lot.
And something (more powerful) you can't do with fields is define them inside an interface. Suppose you want an interface that requires implementing classes to have a certain property:
public interface MyInterface
{
string MyProperty { get; }
}
Note that you do not need to have a setter here. It is entirely up to implementing classes to determine how they should set MyProperty.

Here is a very small example of one way you could use a string property over simply using a string.
Say you have a private variable called:
private string _name;
Now lets say you wanted to make that string read only? In other words, you can't change the value. You could use the following:
public string Name
{
get { return _name; }
}
It can allow you to control access to that value. Alternatively, you can have it so that that variable can only be write only doing the following:
public string Name
{
set { _name = value; }
}
Now if you put it together, it will allow you to set to value or simply get the value. See the following:
public string Name
{
get { return _name; }
set { _name = value; }
}
You may be wondering what the point of that is since it looks like you can do the same thing with a regular string, well of course but this controls direct access to the _name variable from outside classes that aren't derived from said class.
Now what if you wanted to control how that value is set? What if you want to do some calculation or perhaps you wanted to add a prefix or suffix to that value? You do the following:
public string Name
{
get
{
return _name;
}
set
{
if (value.ToLower() == "bilbo")
_name = "Bilbo Baggins";
}
}
Now, if you set the Name property of the class to bilbo, the value of _name will be set to Bilbo Baggins as opposed to if you set the property to Amy, the _name variable will contain simply, amy.
You can do this to guarantee that whatever value that the property is set to is automatically upper or lowercase, or perhaps you can do some validation on the value or something of that sort.
I hope this explains the uses of properties and how they can be useful without making it too complicated.

Properties provide you with more flexibility, especially in .NET. C# shows bias toward properties, so keep that in mind. However, as a general rule, use accessors/mutators when getting or setting needs "processing" or an accompanying action. Use fields for holding values. E.g.,
public class Name
{
public string First;
public string Last;
public string Full{ get { return this.First + " " + this.Last; } }
}

C# internal name behind-the-scenes for getter/setter [duplicate]

This question already has answers here:
Closed 11 years ago.
Possible Duplicate:
Can I create an automatic property (no private member) with get and set code?
Access automatic property - c#
I've worked with explicit getters / setters such as
private bool myField;
public bool MyField
{ get { return myField; }
set { myField = value; }
}
Now, working with C# .net 4.0, you have the ability to abbreviate such as
public bool MyField
{ get; set; }
Now, if I want to override only the SET portion, what is the INTERNAL reference I should be referencing... in the first sample, I know I am explicitly referring to the private of "myField", but with the second version, what am I referencing? Does the compiler just throw an implied "_" such as _MyField as the private side of the element?

class Parent
{
public virtual bool MyField { get; set; }
}
class Child : Parent
{
public override bool MyField
{
//ommitting get portion
set
{
//other custom code goes here
base.MyField = value;
}
}
}
Here a class inherits from a class with a property an overrides only the setter. Alternatively you could override the getter and just leave it as return base.MyField to not change the functionality.
Edit:
The issue was raised that when doing this the half that was left out (the get in my example) wouldn't exist in the child class, making the property read/write only. That is not the case, the half that is left out simply inherits its functionality from its parent. See the following addition to my example to demonstrate.
Child c = new Child();
c.MyField = true;
if (c.MyField)
{
Console.WriteLine("hi");
}
(This will indeed print "hi", no errors compile or runtime.)

whatever the compiler does in this case is an implementation detail which can change in the future without further notice!
Thus I strongly recommend to not make your code depend on such an implementation detail and just use the first option (override both accessors and have field to explicitely back the property) in this case...

You would access the property in the same way, using MyField. However, if you did not want code outside the class to be able to set the property, you can use:
public bool MyField { get; private set; }

Getters, setters, and properties best practices. Java vs. C#

I'm taking a C# class right now and I'm trying to find out the best way of doing things. I come from a Java background and so I'm only familiar with Java best-practices; I'm a C# novice!
In Java if I have a private property, I do this;
private String name;
public void setName(String name) {
this.name = name;
}
public String getName() {
return this.name;
}
In C#, I see that there are many ways of doing this.
I can do it like Java:
private string name;
public void setName(string name) {
this.name = name;
}
public string getName() {
return this.name;
}
Or I can do it this way:
private string name;
public string Name {
get { return name; }
set { name = value; }
}
Or:
public string Name { get; set; }
Which one should I use, and what are the caveats or subtleties involved with each approach? When creating classes, I am following general best-practices that I know from Java (especially reading Effective Java). So for example, I am favoring immutability (providing setters only when necessary). I'm just curious to see how these practices fit in with the various ways of providing setters and getters in C#; essentially, how would I translate best-practices from the Java world into C#?
EDIT
I was posting this as a comment to Jon Skeet's answer but then it got long:
What about a non-trivial property (i.e., with significant processing and validation perhaps)? Could I still expose it via a public property but with the logic encapsulated in get and set? Why would/should I do this over having dedicated setter and getter methods (with associated processing and validation logic).

Pre-C# 6
I'd use the last of these, for a trivial property. Note that I'd call this a public property as both the getters and setters are public.
Immutability is a bit of a pain with automatically implemented properties - you can't write an auto-property which only has a getter; the closest you can come is:
public string Foo { get; private set; }
which isn't really immutable... just immutable outside your class. So you may wish to use a real read-only property instead:
private readonly string foo;
public string Foo { get { return foo; } }
You definitely don't want to write getName() and setName(). In some cases it makes sense to write Get/Set methods rather than using properties, particularly if they could be expensive and you wish to emphasize that. However, you'd want to follow the .NET naming convention of PascalCase for methods, and you wouldn't want a trivial property like this to be implemented with normal methods anyway - a property is much more idiomatic here.
C# 6
Hooray, we finally have proper read-only automatically implemented properties:
// This can only be assigned to within the constructor
public string Foo { get; }
Likewise for read-only properties which do need to do some work, you can use member-bodied properties:
public double Area => height * width;

If all you need is a variable to store some data:
public string Name { get; set; }
Want to make it appear read-only?
public string Name { get; private set; }
Or even better...
private readonly string _name;
...
public string Name { get { return _name; } }
Want to do some value checking before assigning the property?
public string Name
{
get { return m_name; }
set
{
if (value == null)
throw new ArgumentNullException("value");
m_name = value;
}
}
In general, the GetXyz() and SetXyz() are only used in certain cases, and you just have to use your gut on when it feels right. In general, I would say that I expect most get/set properties to not contain a lot of logic and have very few, if any, unexpected side effects. If reading a property value requires invoking a service or getting input from a user in order to build the object that I'm requesting, then I would wrap it into a method, and call it something like BuildXyz(), rather than GetXyz().

Use properties in C#, not get/set methods. They are there for your convenience and it is idiomatic.
As for your two C# examples, one is simply syntactic sugar for the other. Use the auto property if all you need is a simple wrapper around an instance variable, use the full version when you need to add logic in the getter and/or setter.

In C# favor properties for exposing private fields for get and/or set. The thie form you mention is an autoproperty where the get and set automatically generate a hidden pivot backing field for you.
I favor auto properties when possible but you should never do a set/get method pair in C#.

public string Name { get; set; }
This is simply a auto-implemented property, and is technically the same as a normal property. A backing field will be created when compiling.
All properties are eventually converted to functions, so the actual compiled implementation in the end is the same as you are used to in Java.
Use auto-implemented properties when you don't have to do specific operations on the backing field. Use a ordinary property otherwise. Use get and set functions when the operation has side effects or is computationally expensive, use properties otherwise.

Regardless of which way you choose in C# the end result is the same. You will get a backinng variable with separate getter and setter methods. By using properties you are following best practices and so it's a matter of how verbose you want to get.
Personally I would choose auto-properties, the last version: public string Name { get; set; }, since they take up the least amount of space. And you can always expand these in the future if you need add something like validation.

Whenever possible I prefer public string Name { get; set; } as it's terse and easily readable. However, there may be times when this one is necessary
private string name;
public string Name {
get { return name; }
set { name = value; }
}

In C# the preferred way is through properties rather than getX() and setX() methods. Also, note that C# does not require that properties have both a get and a set - you can have get-only properties and set-only properties.
public boolean MyProperty
{
get { return something; }
}
public boolean MyProperty
{
set { this.something = value; }
}

First let me try to explain what you wrote:
// private member -- not a property
private string name;
/// public method -- not a property
public void setName(string name) {
this.name = name;
}
/// public method -- not a property
public string getName() {
return this.name;
}
// yes it is property structure before .Net 3.0
private string name;
public string Name {
get { return name; }
set { name = value; }
}
This structure is also used nowadays but it is most suitable if you want to do some extra functionality, for instance when a value is set you can it to parse to capitalize it and save it in private member for alter internal use.
With .net framework 3.0
// this style is introduced, which is more common, and suppose to be best
public string Name { get; set; }
//You can more customize it
public string Name
{
get;
private set; // means value could be set internally, and accessed through out
}
Wish you better luck in C#

As mentioned, all of these approaches result in the same outcome. The most important thing is that you pick a convention and stick with it. I prefer using the last two property examples.

like most of the answers here, use Automatic properties. Intuitive, less lines of code and it is more clean. If you should serialize your class, mark the class [Serializable]/ with [DataConract] attribute. And if you are using [DataContract] mark the member with
[DataMember(Name="aMoreFriendlyName")]
public string Name { get; set; }
Private or public setter depends on your preference.
Also note that automatic properties require both getters and setters(public or private).
/*this is invalid*/
public string Name
{
get;
/* setter omitted to prove the point*/
}
Alternatively, if you only want get/set, create a backing field yourself

Which one should I use, and what are the caveats or subtleties involved with each approach?
When going with properties there is one caveat that has not been mentioned yet: With properties you cannot have any parametrization of your getters or setters.
For example imagine you want to retrieve a list items and want to also apply a filter at the same time. With a get-method you could write something like:
obj.getItems(filter);
In contrast, with a property you are forced to first return all items
obj.items
and then apply the filter in the next step or you have to add dedicated properties that expose items filtered by different criteria, which soon bloats your API:
obj.itemsFilteredByX
obj.itemsFilteredByY
What sometimes can be a nuisance is when you started with a property, e.g. obj.items and then later discovered that getter- or setter-parametrization is needed or would make things easier for the class-API user. You would now need to either rewrite your API and modify all those places in your code that access this property or find an alternative solution. In contrast, with a get-method, e.g. obj.getItems(), you can simply extend your method's signature to accept an optional "configuration" object e.g. obj.getItems(options) without having to rewrite all those places that call your method.
That being said, (auto-implemented) properties in C# are still very useful shortcuts (for the various reasons mentioned here) since most of the time parametrization may not be needed – but this caveat stands.

Accessing members in your own class: use (auto)properties or not?

I've created this "question" as a community-wiki, because there is no right or wrong answer. I only would like to know how the community feels about this specific issue.
When you have a class with instance variables, and you also created properties that are simply getters and setters for these instance variables, should you use the properties inside your own class, or should you always use the instance variable?
Having auto-properties in C# 3.0 made this an even harder decision.
Using properties:
public class MyClass
{
private string _name;
// could be an auto-property of-course
public string Name { get { return _name; } set { _name = value; } }
public void Action()
{
string localVar = Name;
// ...
Name = "someValue";
// ...
}
}
Using instance variables:
public class MyClass
{
private string _name;
public string Name { get { return _name; } set { _name = value; } }
public void Action()
{
string localVar = _name;
// ...
_name = "someValue";
// ...
}
}
(for those who hate member prefixes, I apologize)
Personally, I always use the latter (instance variables), because I feel that properties should only be used by other classes, not yourself. That's why I mostly stay away from auto-properties as well.
Of course, things change when the property setter (or getter) does a little more than just wrapping the instance variable.
Are there compelling reasons to pick one or the other?

I always use instance variables as well. The reason is because properties might be doing stuff like validating arguments (like in a setter) for not null or not empty. If you're using the variable inside your class code, there's no need to go through the extra overhead of those checks (assuming you know the variable value is valid). The properties could be doing other things as well (logging, for example), that are important for the public API, but not for internal usage, so again, it's better to avoid the overhead and just use the instance variable in my opinion.

I think it becomes more difficult to change the internal implementation if the code uses its own public interface.
Difficult to explain but consider these expressions:
mTotalPrice = mPrice * mQuantity;
mTotalPrice = Price * Quantity;
What to do in the second expression if I need to change the internals to express all prices in € instead of $ (without affecting the public interface which still uses $)?
One solution is to make the expression more complex by adding the opposite of the change in the property.
mTotalPrice = Price / Rate * Quantity
The other solution is to start to use the private field instead.
mTotalPrice = mPrice * Quantity
In the end you get a mix of private and public use. The only way to get consistent use is to always use the private field.

I don't like prefixing members either, but actually I find I can write something like this accidently and not spot it until run time. Which kinda tempts me to avoid using properties where they're not necessary... but I still do, currently!
Public String MyString
{
{ get { return this.MyString; } } //<== Stack Overflow
{ set { this.myString = value; } }
}
private String myString;

I think that there is no difference between these two approaches.
Auto-implemented properties is just a quick way to access private members which are created any way.
Example from MSDN:
class Customer
{
// Auto-Impl Properties for trivial get and set
public double TotalPurchases { get; set; }
public string Name { get; set; }
public int CustomerID { get; set; }
// Constructor
public Customer(double purchases, string name, int ID)
{
TotalPurchases = purchases;
Name = name;
CustomerID = ID;
}
// Methods
public string GetContactInfo() {return "ContactInfo";}
public string GetTransactionHistory() {return "History";}
// .. Additional methods, events, etc.
}

99% of the time I use the property rather then the instance variable. In the past, I've worked with a lot of code that used the instance variable and when there was a bug associated with that variable, I had to put a breakpoint on every line of code that referenced it.
I decided to use properties instead, either public or private, to wrap around the instance variable. Doing this means that I only have to put a breakpoint in the getter/setter of the property if I need to debug an issue with the instance variable, rather then having (potentially) a lot of breakpoints scattered all over the code.