public void EmitConvert(Type from, Type to, bool check = false)
{
if (from == to)
{
return;
}
if (!from.IsValueType)
{
if (!to.IsValueType)
{
Il.Castclass(to);
}
else
{
if (from != typeof(object) && !(from == typeof(Enum) && to.IsEnum))
{
throw new InvalidCastException("Cannot cast an object of type '" + from + "' to type '" + to + "'");
}
Il.Unbox_Any(to);
}
}
else
{
if (!to.IsValueType)
{
if (to != typeof(object) && !(to == typeof(Enum) && from.IsEnum))
{
throw new InvalidCastException("Cannot cast an object of type '" + from + "' to type '" + to + "'");
}
Il.Box(from);
}
else
{
if (to.IsNullable())
{
var toArgument = to.GetGenericArguments()[0];
if (from.IsNullable())
{
var fromArgument = from.GetGenericArguments()[0];
using (var temp = DeclareLocal(from))
{
Il.Stloc(temp);
Il.Ldloca(temp);
EmitHasValueAccess(from);
var valueIsNullLabel = Il.DefineLabel("valueIsNull");
Il.Brfalse(valueIsNullLabel);
Il.Ldloca(temp);
EmitValueAccess(from);
if (toArgument != fromArgument)
{
EmitConvert(fromArgument, toArgument, check);
}
Il.Newobj(to.GetConstructor(new[] { toArgument }));
var doneLabel = Il.DefineLabel("done");
Il.Br(doneLabel);
MarkLabelAndSurroundWithSP(valueIsNullLabel);
EmitLoadDefaultValue(to);
MarkLabelAndSurroundWithSP(doneLabel);
}
}
else
{
if (toArgument != from)
{
EmitConvert(from, toArgument, check);
}
Il.Newobj(to.GetConstructor(new[] { toArgument }));
}
}
else if (from.IsNullable())
{
var fromArgument = from.GetGenericArguments()[0];
using (var temp = DeclareLocal(from))
{
Il.Stloc(temp);
Il.Ldloca(temp);
var valueIsNullLabel = Il.DefineLabel("valueIsNull");
Il.Brfalse(valueIsNullLabel);
Il.Ldloca(temp);
EmitValueAccess(from);
if (to != fromArgument)
{
EmitConvert(fromArgument, to, check);
}
var doneLabel = Il.DefineLabel("done");
Il.Br(doneLabel);
MarkLabelAndSurroundWithSP(valueIsNullLabel);
EmitLoadDefaultValue(to);
MarkLabelAndSurroundWithSP(doneLabel);
}
}
else if (to.IsEnum || to == typeof(Enum))
{
EmitConvert(from, typeof(int), check);
}
else if (from.IsEnum || from == typeof(Enum))
{
EmitConvert(typeof(int), to, check);
}
else
{
if (!check)
{
EmitConvertValue(Il, from, to);
}
else
{
EmitConvertValueChecked(Il, from, to);
}
}
}
}
}