ObjectDumper re-loaded

Sometimes in history a star flashes for a short moment to shade for the next. The same happened to the class ObjectDumper which is quite a handy class for writing NUnit Test cases – published one time in a microsoft sample – and after that never found again.

The performance of that class used with NUnit was terrible, because the ObjectDumper wrote directly to the Console Out Stream. That forced NUnit to refresh the UI again and again. I improved the ObjectDumper, so that it takes a StringBuilder and write the complete output to the Console in one step. That’s faster.

You can output the content of every object using the following syntax:

ObjectDumper.Write (object you want to output);

Cheers
- Gerhard

---

public class ObjectDumper {
    
    public static void Write(object o) {
        Write(o, 0);
    }
    
    public static void Write(object o, int depth) {
        ObjectDumper dumper = new ObjectDumper(depth);
        dumper.WriteObject(null, o);
        Console.Write(dumper.ToString());
    }
    
    private StringBuilder builder = new StringBuilder();
    
    int pos;
    int level;
    int depth;
    
    public override string ToString()
    {
        return builder.ToString();
    }
    
    private ObjectDumper(int depth) {
        this.depth = depth;
    }
    
    private void Write(string s) {
        if (s != null) {
            builder.Append(s);
            pos += s.Length;
        }
    }
    
    private void WriteIndent() {
        builder.Append(' ', level * 3);
    }
    
    private void WriteLine() {
        builder.AppendLine();
        pos = 0;
    }
    
    private void WriteTab() {
        Write("\t");
    }
    
    private void WriteObject(string prefix, object o) {
        
        if (o == null || o is ValueType || o is string) {
            WriteIndent();
            Write(prefix);
            WriteValue(o);
            WriteLine();
        }
        else if (o is IEnumerable) {
            foreach (object element in (IEnumerable)o) {
                if (element is IEnumerable && !(element is string)) {
                    WriteIndent();
                    Write(prefix);
                    Write("...");
                    WriteLine();
                    if (level < depth) {
                        level++;
                        WriteObject(prefix, element);
                        level--;
                    }
                }
                else {
                    WriteObject(prefix, element);
                }
            }
        }
        else {
            MemberInfo[] members = o.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(o) : p.GetValue(o, 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(o) : p.GetValue(o, 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("{ }");
        }
    }
}