O2 Scripts that Show type Confusion in Action

Casting a TextBox as a Label.cs

var textBox = panel.add_TextBox(true);
textBox.set_Text("hello world");
var label = (Label)textBox.castViaTypeConfusion<Label>();
return label.FlatStyle.str();  // will return a value that depends on some part of the TextBox object raw value

//return textBox.FlatStyle; // doesn't compile: System.Windows.Forms.TextBox' does not contain a definition for 'FlatStyle' and no extension method 'FlatStyle' accepting a first argument of type 

//O2File:_Extra_methods_TypeConfusion.cs

Creating the DLL that does the type confusion.cs

 public static string create_DLL_TO_castViaTypeConfusion()
        {
            var assemblyName = "TypeConfusion";
            var dllName = assemblyName + ".dll";
            var appDomain = AppDomain.CurrentDomain;
            var targetDir = "".tempDir(false);
            var targetFile = targetDir.pathCombine(dllName);
            if (targetFile.fileExists())
                return targetFile;

            var assemblyBuilder = assemblyName.assemblyBuilder_forSave(targetDir);  // use this if wanting to Save the assembly created
            var moduleBuilder = assemblyBuilder.dynamicModule(dllName);
            var typeBuilder = moduleBuilder.dynamicType(assemblyName);

            var methodBuilder = typeBuilder.dynamicMethod("castObjectIntoType", null, typeof(object));

            var genericParameters = methodBuilder.DefineGenericParameters("T");
            var returnType = genericParameters[0];
            methodBuilder.SetReturnType(returnType);

            var ilGenerator = methodBuilder.il();
            ilGenerator.DeclareLocal(typeof(object));
            ilGenerator.Emit(OpCodes.Ldarg_1);
            ilGenerator.Emit(OpCodes.Stloc_0);
            ilGenerator.Emit(OpCodes.Ldloc_0);
            ilGenerator.ret();

            var type = typeBuilder.create();

            assemblyBuilder.Save(dllName);
            return targetFile;
        }

Extension method.cs

//O2File:DynamicTypes.cs 
//O2Tag_DontAddExtraO2Files
//O2Ref:TypeConfusion.dll

namespace O2.XRules.Database.Utils
{	
			
	public static class _extra_TypeConfusion_ExtensionMethods
	{			
		public static T castViaTypeConfusion<T>(this object _objectToCast)
		{
			return (T)new TypeConfusion().castObjectIntoType<T>(_objectToCast);
		}

Using a String as String builder.cs

string aString = "1234";
var aStringBuilder = (StringBuilder)aString.castViaTypeConfusion<StringBuilder>(); 
//the next line will trick the compiler (and runtime engine) into thinking that the object returned by castViaTypeConfusion is a StringBuilder

return aStringBuilder;  		// returns "1234"

return aStringBuilder.Equals(aString);  // returns true

//other examples:

// aStringBuilder == aString;			 									 // won't compile due to : Operator '==' cannot be applied to operands of type 'System.Text.StringBuilder' and 'string'
//var aStringBuilder = (String)aString.castViaTypeConfusion<StringBuilder>(); 	// won't compile due to : Cannot convert type 'System.Text.StringBuilder' to 'string'

aStringBuilder = aString.castViaTypeConfusion<StringBuilder>(); // the cast will be done to the value of the generic type
try
{
	aStringBuilder.AppendLine("12");		// this will compile since the compiler thinks that aStringBuilder is a StringBuilder
}
catch(Exception ex)
{
	ex.logStackTrace(); // catches error:
								
						//    	at System.Text.StringBuilder.Append(String value)
   						//		at System.Text.StringBuilder.AppendLine(String value)
   						//		at DynamicType.dynamicMethod(Panel panel) in 
}
//Int32.Parse(aStringBuilder);  // doesn't compile
var aNumber = Int32.Parse((string)(object)(aStringBuilder));
return aNumber; // returns the int: 1234

//here is another way to convert into int
return ((string)(object)(aStringBuilder)).toInt();	// returns the int: 1234


//doing the cast without using the castViaTypeConfusion extension method:
var sbBuilder = (StringBuilder)new TypeConfusion().castObjectIntoType<StringBuilder>(aString);

//using System.Text
//O2Ref:TypeConfusion.dll

//_O2Tag_DontAddExtraO2Files