What is the best way to dump entire objects to a l

Question

So for viewing a current object's state at runtime, I really like what the Visual Studio Immediate window gives me. Just doing a simple

? objectname

Will give me a nicely formatted 'dump' of the object.

Is there an easy way to do this in code, so I can do something similar when logging?

Answer 1

Following is another version that does the same thing (and handle nested properties), which I think is simpler (no dependencies on external libraries and can be modified easily to do things other than logging):

public class ObjectDumper
{
    public static string Dump(object obj)
    {
        return new ObjectDumper().DumpObject(obj);
    }

    StringBuilder _dumpBuilder = new StringBuilder();

    string DumpObject(object obj)
    {
        DumpObject(obj, 0);
        return _dumpBuilder.ToString();
    }

    void DumpObject(object obj, int nestingLevel = 0)
    {
        var nestingSpaces = "".PadLeft(nestingLevel * 4);

        if (obj == null)
        {
            _dumpBuilder.AppendFormat("{0}null\n", nestingSpaces);
        }
        else if (obj is string || obj.GetType().IsPrimitive)
        {
            _dumpBuilder.AppendFormat("{0}{1}\n", nestingSpaces, obj);
        }
        else if (ImplementsDictionary(obj.GetType()))
        {
            using (var e = ((dynamic)obj).GetEnumerator())
            {
                var enumerator = (IEnumerator)e;
                while (enumerator.MoveNext())
                {
                    dynamic p = enumerator.Current;

                    var key = p.Key;
                    var value = p.Value;
                    _dumpBuilder.AppendFormat("{0}{1} ({2})\n", nestingSpaces, key, value != null ? value.GetType().ToString() : "<null>");
                    DumpObject(value, nestingLevel + 1);
                }
            }
        }
        else if (obj is IEnumerable)
        {
            foreach (dynamic p in obj as IEnumerable)
            {
                DumpObject(p, nestingLevel);
            }
        }
        else
        {
            foreach (PropertyDescriptor descriptor in TypeDescriptor.GetProperties(obj))
            {
                string name = descriptor.Name;
                object value = descriptor.GetValue(obj);

                _dumpBuilder.AppendFormat("{0}{1} ({2})\n", nestingSpaces, name, value != null ? value.GetType().ToString() : "<null>");
                DumpObject(value, nestingLevel + 1);
            }
        }
    }

    bool ImplementsDictionary(Type t)
    {
        return t.GetInterfaces().Any(i => i.Name.Contains("IDictionary"));
    }
}

Answer 2

I found a library called ObjectPrinter which allows to easily dump objects and collections to strings (and more). It does exactly what I needed.

Answer 3

You can write your own WriteLine method-

public static void WriteLine<T>(T obj)
    {
        var t = typeof(T);
        var props = t.GetProperties();
        StringBuilder sb = new StringBuilder();
        foreach (var item in props)
        {
            sb.Append($"{item.Name}:{item.GetValue(obj,null)}; ");
        }
        sb.AppendLine();
        Console.WriteLine(sb.ToString());
    }

Use it like-

WriteLine(myObject);

To write a collection we can use-

 var ifaces = t.GetInterfaces();
        if (ifaces.Any(o => o.Name.StartsWith("ICollection")))
        {

            dynamic lst = t.GetMethod("GetEnumerator").Invoke(obj, null);
            while (lst.MoveNext())
            {
                WriteLine(lst.Current);
            }
        }   

The method may look like-

 public static void WriteLine<T>(T obj)
    {
        var t = typeof(T);
        var ifaces = t.GetInterfaces();
        if (ifaces.Any(o => o.Name.StartsWith("ICollection")))
        {

            dynamic lst = t.GetMethod("GetEnumerator").Invoke(obj, null);
            while (lst.MoveNext())
            {
                WriteLine(lst.Current);
            }
        }            
        else if (t.GetProperties().Any())
        {
            var props = t.GetProperties();
            StringBuilder sb = new StringBuilder();
            foreach (var item in props)
            {
                sb.Append($"{item.Name}:{item.GetValue(obj, null)}; ");
            }
            sb.AppendLine();
            Console.WriteLine(sb.ToString());
        }
    }

Using if, else if and checking interfaces, attributes, base type, etc. and recursion (as this is a recursive method) in this way we may achieve an object dumper, but it is tedious for sure. Using the object dumper from Microsoft's LINQ Sample would save your time.

Answer 4

You could base something on the ObjectDumper code that ships with the Linq samples.
Have also a look at the answer of this related question to get a sample.

Answer 5

For a larger object graph, I second the use of Json but with a slightly different strategy. First I have a static class that is easy to call and with a static method that wraps the Json conversion (note: could make this an extension method).

using Newtonsoft.Json;

public static class F
{
    public static string Dump(object obj)
    {
        return JsonConvert.SerializeObject(obj);
    }
}

Then in your Immediate Window,

var lookHere = F.Dump(myobj);

lookHere will auto-show up in the Locals window prepended with a $ or you can add a watch to it. On the right hand side of the Value column in the inspector, there is a magnifying glass with a dropdown caret beside it. Choose the dropdown caret and choose Json visualizer.

I am using Visual Studio 2013.

Answer 6

You could use Visual Studio Immediate Window

Just paste this (change actual to your object name obviously):

Newtonsoft.Json.JsonConvert.SerializeObject(actual);

It should print object in JSON

You should be able to copy it over textmechanic text tool or notepad++ and replace escaped quotes (\") with " and newlines (\r\n) with empty space, then remove double quotes (") from beginning and end and paste it to jsbeautifier to make it more readable.

UPDATE to OP's comment

public static class Dumper
{
    public static void Dump(this object obj)
    {
        Console.WriteLine(Newtonsoft.Json.JsonConvert.SerializeObject(obj)); // your logger
    }
}

this should allow you to dump any object.

Hope this saves you some time.