public static void EmitNullableExpression(this CompilationContext context, LocalBuilder local,
Action <CompilationContext> nonNullExpression, Action <CompilationContext> nullExpression)
{
var label = context.DefineLabel();
if (local.LocalType.IsNullable())
{
#if NetCore
var variableType = local.LocalType.GetTypeInfo();
#else
var variableType = local.LocalType;
#endif
context.Emit(OpCodes.Ldloca, local);
context.EmitCall(variableType.GetProperty("HasValue").GetGetMethod());
context.Emit(OpCodes.Brfalse, label);
context.Emit(OpCodes.Ldloca, local);
context.EmitCall(variableType.GetProperty("Value").GetGetMethod());
context.CurrentType = variableType.GetGenericArguments()[0];
}
else
{
context.Emit(OpCodes.Ldloc, local);
context.Emit(OpCodes.Ldnull);
context.EmitCall(_referenceEqualsMethod);
context.Emit(OpCodes.Brtrue, label);
context.Emit(OpCodes.Ldloc, local);
context.CurrentType = local.LocalType;
}
nonNullExpression(context);
var labelEnd = context.DefineLabel();
context.Emit(OpCodes.Br, labelEnd);
context.MakeLabel(label);
nullExpression(context);
context.MakeLabel(labelEnd);
}
public override void Emit(Type sourceType, Type targetType, CompilationContext context)
{
#if NetCore
var reflectingTargetType = targetType.GetTypeInfo();
#else
var reflectingTargetType = targetType;
#endif
var target = context.DeclareLocal(targetType);
var local = context.DeclareLocal(sourceType);
context.Emit(OpCodes.Stloc, local);
if (targetType.IsNullable())
{
var labelEnd = context.DefineLabel();
var labelFirst = context.DefineLabel();
// if(source == null)
context.Emit(OpCodes.Ldloc, local);
context.Emit(OpCodes.Brtrue, labelFirst);
// target = null;
context.Emit(OpCodes.Ldloca, target);
context.Emit(OpCodes.Initobj, targetType);
// goto end;
context.Emit(OpCodes.Br, labelEnd);
context.MakeLabel(labelFirst);
// if(string.IsNullOrWhiteSpace(source))
var labelSecond = context.DefineLabel();
context.Emit(OpCodes.Ldloc, local);
context.EmitCall(_checkEmptyMethod);
context.Emit(OpCodes.Brfalse, labelSecond);
// target = new Nullable<T>(default(T));
context.EmitDefault(reflectingTargetType.GetGenericArguments()[0]);
context.Emit(OpCodes.Newobj, reflectingTargetType.GetConstructors()[0]);
context.Emit(OpCodes.Stloc, target);
// goto end;
context.Emit(OpCodes.Br, labelEnd);
context.MakeLabel(labelSecond);
// target = new Nullable<$EnumType$>(($EnumType$)Enum.Parse(typeof($EnumType$),source));
// or
// target = new Nullable<$TargetType$>($TargetType$.Parse(source));
var underlingType = reflectingTargetType.GetGenericArguments()[0];
#if NetCore
if (underlingType.GetTypeInfo().IsEnum)
#else
if (underlingType.IsEnum)
#endif
{
context.EmitTypeOf(underlingType);
}
context.Emit(OpCodes.Ldloc, local);
context.EmitCall(_stringTrimMethod);
context.EmitCall(GetConvertMethod(underlingType));
context.EmitCast(underlingType);
context.Emit(OpCodes.Newobj, reflectingTargetType.GetConstructors()[0]);
context.Emit(OpCodes.Stloc, target);
context.MakeLabel(labelEnd);
context.Emit(OpCodes.Ldloc, target);
}
else
{
// if(!string.IsNullOrWhiteSpace(source))
var label = context.DefineLabel();
context.Emit(OpCodes.Ldloc, local);
context.EmitCall(_checkEmptyMethod);
context.Emit(OpCodes.Brtrue, label);
// target = ($EnumType$)Enum.Parse(typeof($EnumType$),source);
// or
// target = $TargetType$.Parse(source);
if (reflectingTargetType.IsEnum)
{
context.EmitTypeOf(targetType);
}
context.Emit(OpCodes.Ldloc, local);
context.EmitCall(_stringTrimMethod);
context.EmitCall(GetConvertMethod(targetType));
context.EmitCast(targetType);
context.Emit(OpCodes.Stloc, target);
// goto end;
var labelEnd = context.DefineLabel();
context.Emit(OpCodes.Br, labelEnd);
// target = default(T);
context.MakeLabel(label);
context.EmitDefault(targetType);
context.Emit(OpCodes.Stloc, target);
context.MakeLabel(labelEnd);
context.Emit(OpCodes.Ldloc, target);
}
}
public override void Emit(Type sourceType, Type targetType, CompilationContext context)
{
#if NETSTANDARD
var reflectingTargetType = targetType.GetTypeInfo();
#else
var reflectingTargetType = targetType;
#endif
context.EmitCast(typeof(IEnumerable <>).MakeGenericType(_sourceElementType));
_invokerBuilder.Emit(context);
if (reflectingTargetType.IsGenericType)
{
var genericTypeDefinition = targetType.GetGenericTypeDefinition();
if (genericTypeDefinition == typeof(IList <>) || genericTypeDefinition == typeof(ICollection <>) || genericTypeDefinition == typeof(IEnumerable <>))
{
context.EmitCast(targetType);
context.CurrentType = targetType;
return;
}
}
else if (targetType.IsArray)
{
context.EmitCast(targetType);
context.CurrentType = targetType;
return;
}
var labelNull = context.DefineLabel();
var labelComplete = context.DefineLabel();
var local = context.DeclareLocal(context.CurrentType);
context.Emit(OpCodes.Stloc, local);
context.Emit(OpCodes.Ldloc, local);
context.Emit(OpCodes.Brfalse, labelNull);
context.Emit(OpCodes.Ldloc, local);
if (targetType.IsEnumerable(out var targetElementType))
{
var constructor = reflectingTargetType.GetConstructor(new[] { typeof(IEnumerable <>).MakeGenericType(targetElementType) }) ??
reflectingTargetType.GetConstructor(new[] { typeof(IList <>).MakeGenericType(targetElementType) }) ??
reflectingTargetType.GetConstructor(new[] { typeof(ICollection <>).MakeGenericType(targetElementType) }) ??
reflectingTargetType.GetConstructor(new[] { targetElementType.MakeArrayType() });
if (constructor != null)
{
context.EmitCast(constructor.GetParameters()[0].ParameterType);
context.Emit(OpCodes.Newobj, constructor);
}
else
{
var defaultConstructor = reflectingTargetType.GetConstructor(Type.EmptyTypes);
var addMethod = reflectingTargetType.GetMethods(BindingFlags.Instance | BindingFlags.Public).Where(method =>
{
if (method.Name != "Add")
{
return(false);
}
var parameters = method.GetParameters();
return(parameters.Length == 1 && parameters[0].ParameterType == targetElementType);
}).FirstOrDefault();
if (defaultConstructor != null && addMethod != null)
{
var targetArrayType = targetElementType.MakeArrayType();
var targetArray = context.DeclareLocal(targetArrayType);
var targetInstance = context.DeclareLocal(targetType);
var index = context.DeclareLocal(typeof(int));
context.EmitCast(targetArrayType);
context.Emit(OpCodes.Stloc, targetArray);
context.Emit(OpCodes.Newobj, defaultConstructor);
context.Emit(OpCodes.Stloc, targetInstance);
// var i = 0;
context.Emit(OpCodes.Ldc_I4_0);
context.Emit(OpCodes.Stloc, index);
var labelEnd = context.DefineLabel();
context.Emit(OpCodes.Br_S, labelEnd);
var labelStart = context.DefineLabel();
context.MakeLabel(labelStart);
// target.Add(array[i]);
context.Emit(OpCodes.Ldloc, targetInstance);
context.Emit(OpCodes.Ldloc, targetArray);
context.Emit(OpCodes.Ldloc, index);
#if NETSTANDARD
var targetElementTypeInfo = targetElementType.GetTypeInfo();
if (targetElementTypeInfo.IsValueType && !targetElementTypeInfo.IsPrimitive)
#else
if (targetElementType.IsValueType && !targetElementType.IsPrimitive)
#endif
{
context.Emit(OpCodes.Ldelema, targetElementType);
}
else
{
context.Emit(OpCodes.Ldelem, targetElementType);
}
context.EmitCall(addMethod);
// i++
context.Emit(OpCodes.Ldloc, index);
context.Emit(OpCodes.Ldc_I4_1);
context.Emit(OpCodes.Add);
context.Emit(OpCodes.Stloc, index);
context.MakeLabel(labelEnd);
context.Emit(OpCodes.Ldloc, index);
context.Emit(OpCodes.Ldloc, targetArray);
context.Emit(OpCodes.Ldlen);
context.Emit(OpCodes.Conv_I4);
context.Emit(OpCodes.Blt_S, labelStart);
context.Emit(OpCodes.Ldloc, targetInstance);
}
}
}
context.Emit(OpCodes.Br_S, labelComplete);
context.MakeLabel(labelNull);
context.Emit(OpCodes.Ldnull);
context.MakeLabel(labelComplete);
context.CurrentType = targetType;
}