object dumper class

Question

I'm looking for a class that can output an object and all its leaf values in a format similar to this:

User
  - Name: Gordon
  - Age : 60
  - WorkAddress
     - Street: 10 Downing Street
     - Town: London
     - Country: UK
  - HomeAddresses[0]
    ...
  - HomeAddresses[1]
    ...

(Or a clearer format). This would be equivalent to:

public class User
{
    public string Name { get;set; }
    public int Age { get;set; }
    public Address WorkAddress { get;set; }
    public List<Address> HomeAddresses { get;set; }
}

public class Address
{
    public string Street { get;set; }
    public string Town { get;set; }
    public string Country { get;set; }
}

A kind of string representation of the PropertyGrid control, minus having to implement a large set of designers for each type.

PHP has something that does this called var_dump. I don't want to use a watch, as this is for printing out.

Could anyone point me to something like this if it exists? Or, write one for a bounty.

Answer 1

The object dumper posted in sgmoore's link:

//Copyright (C) Microsoft Corporation.  All rights reserved.

using System;
using System.IO;
using System.Collections;
using System.Collections.Generic;
using System.Reflection;

// See the ReadMe.html for additional information
public class ObjectDumper {

    public static void Write(object element)
    {
        Write(element, 0);
    }

    public static void Write(object element, int depth)
    {
        Write(element, depth, Console.Out);
    }

    public static void Write(object element, int depth, TextWriter log)
    {
        ObjectDumper dumper = new ObjectDumper(depth);
        dumper.writer = log;
        dumper.WriteObject(null, element);
    }

    TextWriter writer;
    int pos;
    int level;
    int depth;

    private ObjectDumper(int depth)
    {
        this.depth = depth;
    }

    private void Write(string s)
    {
        if (s != null) {
            writer.Write(s);
            pos += s.Length;
        }
    }

    private void WriteIndent()
    {
        for (int i = 0; i < level; i++) writer.Write("  ");
    }

    private void WriteLine()
    {
        writer.WriteLine();
        pos = 0;
    }

    private void WriteTab()
    {
        Write("  ");
        while (pos % 8 != 0) Write(" ");
    }

    private void WriteObject(string prefix, object element)
    {
        if (element == null || element is ValueType || element is string) {
            WriteIndent();
            Write(prefix);
            WriteValue(element);
            WriteLine();
        }
        else {
            IEnumerable enumerableElement = element as IEnumerable;
            if (enumerableElement != null) {
                foreach (object item in enumerableElement) {
                    if (item is IEnumerable && !(item is string)) {
                        WriteIndent();
                        Write(prefix);
                        Write("...");
                        WriteLine();
                        if (level < depth) {
                            level++;
                            WriteObject(prefix, item);
                            level--;
                        }
                    }
                    else {
                        WriteObject(prefix, item);
                    }
                }
            }
            else {
                MemberInfo[] members = element.GetType().GetMembers(BindingFlags.Public | BindingFlags.Instance);
                WriteIndent();
                Write(prefix);
                bool propWritten = false;
                foreach (MemberInfo m in members) {
                    FieldInfo f = m as FieldInfo;
                    PropertyInfo p = m as PropertyInfo;
                    if (f != null || p != null) {
                        if (propWritten) {
                            WriteTab();
                        }
                        else {
                            propWritten = true;
                        }
                        Write(m.Name);
                        Write("=");
                        Type t = f != null ? f.FieldType : p.PropertyType;
                        if (t.IsValueType || t == typeof(string)) {
                            WriteValue(f != null ? f.GetValue(element) : p.GetValue(element, null));
                        }
                        else {
                            if (typeof(IEnumerable).IsAssignableFrom(t)) {
                                Write("...");
                            }
                            else {
                                Write("{ }");
                            }
                        }
                    }
                }
                if (propWritten) WriteLine();
                if (level < depth) {
                    foreach (MemberInfo m in members) {
                        FieldInfo f = m as FieldInfo;
                        PropertyInfo p = m as PropertyInfo;
                        if (f != null || p != null) {
                            Type t = f != null ? f.FieldType : p.PropertyType;
                            if (!(t.IsValueType || t == typeof(string))) {
                                object value = f != null ? f.GetValue(element) : p.GetValue(element, null);
                                if (value != null) {
                                    level++;
                                    WriteObject(m.Name + ": ", value);
                                    level--;
                                }
                            }
                        }
                    }
                }
            }
        }
    }

    private void WriteValue(object o)
    {
        if (o == null) {
            Write("null");
        }
        else if (o is DateTime) {
            Write(((DateTime)o).ToShortDateString());
        }
        else if (o is ValueType || o is string) {
            Write(o.ToString());
        }
        else if (o is IEnumerable) {
            Write("...");
        }
        else {
            Write("{ }");
        }
    }
}

2015 Update

YAML also serves this purpose quite well, this is how it can be done with YamlDotNet

install-package YamlDotNet

    private static void DumpAsYaml(object o)
    {
        var stringBuilder = new StringBuilder();
        var serializer = new Serializer();
        serializer.Serialize(new IndentedTextWriter(new StringWriter(stringBuilder)), o);
        Console.WriteLine(stringBuilder);
    }

Answer 2

You could use the JSON serialiser, which should be easy to read for anyone use to working with JSON

User theUser = new User();
theUser.Name = "Joe";
System.Runtime.Serialization.Json.DataContractJsonSerializer serializer = new System.Runtime.Serialization.Json.DataContractJsonSerializer(myPerson.GetType());
MemoryStream ms = new MemoryStream();
serializer.WriteObject(ms, theUser );
string json = Encoding.Default.GetString(ms.ToArray()); 

Answer 3

Updated 2019

You can find the ObjectDumper project on GitHub. You can also add it via Visual Studio via NuGet package manager.

Answer 4

If you're working with markup, System.Web.ObjectInfo.Print (ASP.NET Web Pages 2) will accomplish this, nicely formatted for HTML.

For example:

@ObjectInfo.Print(new {
    Foo = "Hello",
    Bar = "World",
    Qux = new {
        Number = 42,
    },
})

In a webpage, produces:

Answer 5

Here's a visual studio extension I wrote to do this:

https://visualstudiogallery.msdn.microsoft.com/c6a21c68-f815-4895-999f-cd0885d8774f

in action:

Answer 6

I know this is an old question, but thought I'd throw out an alternative that worked for me, took me about two minutes to do.

Install Newtonsoft Json.NET: http://james.newtonking.com/json

(or nuget version) http://www.nuget.org/packages/newtonsoft.json/

Reference Assembly:

using Newtonsoft.Json;

Dump JSON string to log:

txtResult.Text = JsonConvert.SerializeObject(testObj);

Answer 7

You could write that very easily with a little bit of reflection. Something kind of like:

public void Print(object value, int depth)
{
    foreach(var property in value.GetType().GetProperties())
    {
        var subValue = property.GetValue(value);
        if(subValue is IEnumerable)
        {
             PrintArray(property, (IEnumerable)subValue);
        }
        else
        {
             PrintProperty(property, subValue);
        }         
    }
}

You can write up the PrintArray and PrintProperty methods.

Answer 8

I have a handy T.Dump() Extension method that should be pretty close to the results you're looking for. As its an extension method, its non-invasive and should work on all POCO objects.

Example Usage

var model = new TestModel();
Console.WriteLine(model.Dump());

Example Output

{
    Int: 1,
    String: One,
    DateTime: 2010-04-11,
    Guid: c050437f6fcd46be9b2d0806a0860b3e,
    EmptyIntList: [],
    IntList:
    [
        1,
        2,
        3
    ],
    StringList:
    [
        one,
        two,
        three
    ],
    StringIntMap:
    {
        a: 1,
        b: 2,
        c: 3
    }
}

Answer 9

If you don't feel like copying and pasting Chris S's code, the Visual Studio 2008 samples come with an ObjectDumper.

Drive:\Program Files\Microsoft Visual Studio 9.0\Samples\1033\LinqSamples\ObjectDumper

Answer 10

Here is an alternative:

using System.Reflection;
public void Print(object value)
{
    PropertyInfo[] myPropertyInfo;
    string temp="Properties of "+value+" are:\n";
    myPropertyInfo = value.GetType().GetProperties();
    for (int i = 0; i < myPropertyInfo.Length; i++)
    {
        temp+=myPropertyInfo[i].ToString().PadRight(50)+" = "+myPropertyInfo[i].GetValue(value, null)+"\n";
    }
    MessageBox.Show(temp);
}

(just touching level 1, no depth, but says a lot)

Answer 11

For most classes, you could use the DataContractSerializer

Answer 12

I just came across a similar requirement in a Blazor project, and came up with the following very simple component to output an object's (and it's child objects') data to the screen:

ObjectDumper.razor:

@using Microsoft.AspNetCore.Components
@using Newtonsoft.Json

  <div>
    <button onclick="@DumpVMToConsole">@ButtonText</button>
    <pre id="json">@_objectAsJson</pre>
  </div>


@functions {

  // This component allows the easy visualisation of the values currently held in 
  // an object and its child objects.  Add this component to a page and pass in a 
  // param for the object to monitor, then press the button to see the object's data
  // as nicely formatted JSON
  // Use like this:  <ObjectDumper ObjectToDump="@_billOfLadingVM" />

  [Parameter]
  private object ObjectToDump { get; set; }

  [Parameter]
  private string ButtonText { get; set; } = "Show object's data";

  string _buttonText;

  string _objectAsJson = "";

  public void DumpVMToConsole()
  {
    _objectAsJson = GetObjectAsFormattedJson(ObjectToDump);
    Console.WriteLine(_objectAsJson);
  }

  public string GetObjectAsFormattedJson(object obj)
  {
    return JsonConvert.SerializeObject(
      value: obj, 
      formatting: Formatting.Indented, 
      settings: new JsonSerializerSettings
      {
        PreserveReferencesHandling = PreserveReferencesHandling.Objects
      });
  }

}

You then stick that somewhere on a Blazor page as follows:

<ObjectDumper ObjectToDump="@YourObjectToVisualise" />

Which then renders a button you can press to see the current values of the bound object:

I've stuck that in a GitHub repo: tomRedox/BlazorObjectDumper