How to Automatically Display All Properties of a Class and Their Values in a String

How do I automatically display all properties of a class and their values in a string?

I think you can use a little reflection here. Take a look at Type.GetProperties().

public override string ToString()
{
    return GetType().GetProperties()
        .Select(info => (info.Name, Value: info.GetValue(this, null) ?? "(null)"))
        .Aggregate(
            new StringBuilder(),
            (sb, pair) => sb.AppendLine($"{pair.Name}: {pair.Value}"),
            sb => sb.ToString());
}

How do I automatically display all properties of a class, which is a property in another class?

ClassA has no properties, only fields.

public double PropA = 5;          // Field
public double PropA { get; set; } // Property

_PropertyInfos isn't null, it's empty.

Either convert your fields to properties or start using this.GetType().GetFields() swapping PropertyInfo[] for FieldInfo[].

C#: Printing all properties of an object

The ObjectDumper class has been known to do that. I've never confirmed, but I've always suspected that the immediate window uses that.

EDIT: I just realized, that the code for ObjectDumper is actually on your machine. Go to:

C:/Program Files/Microsoft Visual Studio 9.0/Samples/1033/CSharpSamples.zip

This will unzip to a folder called LinqSamples. In there, there's a project called ObjectDumper. Use that.

How to print all property values of an object without naming the properties explicitly

If you want to

• Write all properties without naming them
• Use it for any Type in a generic way

You can write a quick Reflection utility like this

public static string GetAllProperties(object obj)
{
    return string.Join(" ", obj.GetType()
                                .GetProperties()
                                .Select(prop => prop.GetValue(obj)));
}

And use it like

foreach (Galaxy theGalaxy in theGalaxies)
{
    Console.WriteLine(GetAllProperties(theGalaxy));
}

vb.net list class properties with values

Type.GetMembers returns a list of MemberInfo objects, one per member of the type. However, not all members have values. Fields and properties have values, so if you get the list of just the fields or just the properties, you can ask them for their values. But things like methods don't have a value. You may be able to invoke them and read their return values, but that's different from reading the value of a property or a field.

In other words, you have to work differently with each member, depending on what kind of member it is. Since MemberInfo is the lowest common-denominator, it doesn't have any of the functionality which only works on some of the members. If you want the additional functionality available to you, you'll need to use one of the more specific methods like GetProperties or GetFields.

Since your class contains properties, you probably want to get the list of properties:

Public Class Person
    Public Property Name As String
    Public Property Age As Integer

    Public Overrides Function ToString() As String
        Dim bigStr As String = ""
        For Each p As PropertyInfo In Me.GetType().GetProperties()
            bigStr &= p.Name & " " & p.GetValue(Me)?.ToString()
        Next
        Return bigStr
    End Function
End Class

Print all properties of a Python Class

In this simple case you can use vars():

an = Animal()
attrs = vars(an)
# {'kids': 0, 'name': 'Dog', 'color': 'Spotted', 'age': 10, 'legs': 2, 'smell': 'Alot'}
# now dump this in some way or another
print(', '.join("%s: %s" % item for item in attrs.items()))

If you want to store Python objects on the disk you should look at shelve — Python object persistence.

Printing all variables value from a class

From Implementing toString:

public String toString() {
  StringBuilder result = new StringBuilder();
  String newLine = System.getProperty("line.separator");

  result.append( this.getClass().getName() );
  result.append( " Object {" );
  result.append(newLine);

  //determine fields declared in this class only (no fields of superclass)
  Field[] fields = this.getClass().getDeclaredFields();

  //print field names paired with their values
  for ( Field field : fields  ) {
    result.append("  ");
    try {
      result.append( field.getName() );
      result.append(": ");
      //requires access to private field:
      result.append( field.get(this) );
    } catch ( IllegalAccessException ex ) {
      System.out.println(ex);
    }
    result.append(newLine);
  }
  result.append("}");

  return result.toString();
}

Is there a built-in function to print all the current properties and values of an object?

You are really mixing together two different things.

Use dir(), vars() or the inspect module to get what you are interested in (I use __builtins__ as an example; you can use any object instead).

>>> l = dir(__builtins__)
>>> d = __builtins__.__dict__

Print that dictionary however fancy you like:

>>> print l
['ArithmeticError', 'AssertionError', 'AttributeError',...

or

>>> from pprint import pprint
>>> pprint(l)
['ArithmeticError',
 'AssertionError',
 'AttributeError',
 'BaseException',
 'DeprecationWarning',
...

>>> pprint(d, indent=2)
{ 'ArithmeticError': <type 'exceptions.ArithmeticError'>,
  'AssertionError': <type 'exceptions.AssertionError'>,
  'AttributeError': <type 'exceptions.AttributeError'>,
...
  '_': [ 'ArithmeticError',
         'AssertionError',
         'AttributeError',
         'BaseException',
         'DeprecationWarning',
...

Pretty printing is also available in the interactive debugger as a command:

(Pdb) pp vars()
{'__builtins__': {'ArithmeticError': <type 'exceptions.ArithmeticError'>,
                  'AssertionError': <type 'exceptions.AssertionError'>,
                  'AttributeError': <type 'exceptions.AttributeError'>,
                  'BaseException': <type 'exceptions.BaseException'>,
                  'BufferError': <type 'exceptions.BufferError'>,
                  ...
                  'zip': <built-in function zip>},
 '__file__': 'pass.py',
 '__name__': '__main__'}

What's the best way to print all properties in a list of objects?

Use

String.Join(", ", myList.Select(x => x.name));

For it you have to include System.Linq namespace

EDIT:

If you want to go for Adam's answer after his code do what this

String.Join(", ", myList.Select(x => x.ToString()));

Courtesy Adam Goss comment on answer:

You wouldn't need to call .Select(x => x.ToString()) as it would be called internally by object inside String.Join(), so if you override ToString(), you just call String.Join(", ", myList);

So after his code do what you had thought

String.Join(", ", myList);

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