internal static LambdaExpression GetSetterLambdaExpressionWithNullChecks(this MemberAccessPath memberAccessPath)
{
var instanceType = memberAccessPath.First().ReflectedType;
var valueType = memberAccessPath.Last().GetMemberType();
var value = Expression.Parameter(valueType, "value");
var entryInstance = Expression.Parameter(instanceType, "instance");
var labelTarget = Expression.Label(typeof(void), "label");
Expression accessPath = entryInstance;
var memberAccesses = new List <Expression>();
foreach (var memberAccess in memberAccessPath)
{
if (memberAccess is MethodInfo methodInfo)
{
if (methodInfo.IsGetterMethod())
{
accessPath = Expression.Call(accessPath, methodInfo);
}
else
{
accessPath = Expression.Call(accessPath, methodInfo, value);
}
}
else
{
accessPath = Expression.MakeMemberAccess(accessPath, memberAccess);
}
memberAccesses.Add(accessPath);
}
if (!(accessPath is MethodCallExpression))
{
accessPath = Expression.Assign(accessPath, value);
}
var nullConstant = Expression.Constant(null);
var returnVoid = Expression.Return(labelTarget, typeof(void));
var nullChecks = memberAccesses.Take(memberAccesses.Count - 1).Select(memberAccess =>
{
var equalsNull = Expression.Equal(memberAccess, nullConstant);
return((Expression)Expression.IfThen(equalsNull, returnVoid));
}).ToList();
var exp = Expression.Block
(
nullChecks.Any() ? Expression.Block(nullChecks.ToArray())
: (Expression)Expression.Empty(),
accessPath,
Expression.Label(labelTarget)
);
var delegateType = typeof(Action <,>).MakeGenericType(instanceType, valueType);
return(LambdaExpression.Lambda(delegateType, exp, entryInstance, value));
}
internal static LambdaExpression GetSetterExp(this MemberAccessPath memberAccessPath)
{
var instanceType = memberAccessPath.EntryInstance;
var accessInstance = Expression.Parameter(instanceType, "instance");
Expression accessPath = accessInstance;
if (memberAccessPath.Count == 0)
{
var valueType2 = memberAccessPath.ReturnType;
var value2 = Expression.Parameter(valueType2, "value");
if (instanceType != memberAccessPath.ReturnType)
{
accessPath = Expression.Convert(accessInstance, memberAccessPath.ReturnType);
}
var delegateType2 = typeof(Action <,>).MakeGenericType(instanceType, instanceType);
return(LambdaExpression.Lambda(delegateType2, accessPath, accessInstance, value2));
}
var valueType = memberAccessPath.Last().GetMemberType();
var value = Expression.Parameter(valueType, "value");
var entryMember = memberAccessPath.First();
foreach (var memberAccess in memberAccessPath)
{
if (memberAccess is MethodInfo methodInfo)
{
if (methodInfo.IsGetterMethod())
{
accessPath = Expression.Call(accessPath, methodInfo);
}
else
{
accessPath = Expression.Call(accessPath, (MethodInfo)memberAccess, value);
}
}
else
{
accessPath = Expression.MakeMemberAccess(accessPath, memberAccess);
}
}
if (!(accessPath is MethodCallExpression))
{
accessPath = Expression.Assign(accessPath, value);
}
var delegateType = typeof(Action <,>).MakeGenericType(instanceType, valueType);
return(LambdaExpression.Lambda(delegateType, accessPath, accessInstance, value));
}
internal static LambdaExpression GetGetterLambdaExpressionWithNullChecks(this MemberAccessPath memberAccessPath)
{
var instanceType = memberAccessPath.First().ReflectedType;
var returnType = memberAccessPath.Last().GetMemberType();
var entryInstance = Expression.Parameter(instanceType, "instance");
var labelTarget = Expression.Label(returnType, "label");
Expression accessPath = entryInstance;
var memberAccesses = new List <Expression>();
foreach (var memberAccess in memberAccessPath)
{
if (memberAccess is MethodInfo)
{
accessPath = Expression.Call(accessPath, (MethodInfo)memberAccess);
}
else
{
accessPath = Expression.MakeMemberAccess(accessPath, memberAccess);
}
memberAccesses.Add(accessPath);
}
var nullConstant = Expression.Constant(null);
var returnNull = Expression.Return(labelTarget, Expression.Default(returnType));
var nullChecks = memberAccesses.Take(memberAccesses.Count - 1).Select(memberAccess =>
{
var equalsNull = Expression.Equal(memberAccess, nullConstant);
return((Expression)Expression.IfThen(equalsNull, returnNull));
}).ToList();
var exp = Expression.Block
(
nullChecks.Any() ? Expression.Block(nullChecks.ToArray())
: (Expression)Expression.Empty(),
Expression.Label(labelTarget, memberAccesses.Last())
);
var delegateType = typeof(Func <,>).MakeGenericType(instanceType, returnType);
return(LambdaExpression.Lambda(delegateType, exp, entryInstance));
}
internal static LambdaExpression GetGetterExp(this MemberAccessPath memberAccessPath)
{
var instanceType = memberAccessPath.EntryInstance;
var accessInstance = Expression.Parameter(instanceType, "instance");
Expression accessPath = accessInstance;
if (memberAccessPath.Count == 0)
{
if (instanceType != memberAccessPath.ReturnType)
{
accessPath = Expression.Convert(accessInstance, memberAccessPath.ReturnType);
}
var delegateType2 = typeof(Func <,>).MakeGenericType(instanceType, instanceType);
return(LambdaExpression.Lambda(delegateType2, accessPath, accessInstance));
}
var entryMember = memberAccessPath.First();
var returnType = memberAccessPath.Last().GetMemberType();
foreach (var memberAccess in memberAccessPath)
{
if (memberAccess is MethodInfo mi)
{
accessPath = Expression.Call(accessPath, mi);
}
else
{
if (memberAccess.DeclaringType != accessPath.Type)
{
accessPath = Expression.Convert(accessPath, memberAccess.DeclaringType);
}
accessPath = Expression.MakeMemberAccess(accessPath, memberAccess);
}
}
var delegateType = typeof(Func <,>).MakeGenericType(instanceType, returnType);
return(LambdaExpression.Lambda(delegateType, accessPath, accessInstance));
}
internal static LambdaExpression GetSetterLambdaExpression(this MemberAccessPath memberAccessPath)
{
var instanceType = memberAccessPath.First().ReflectedType;
var valueType = memberAccessPath.Last().GetMemberType();
var value = Expression.Parameter(valueType, "value");
var accessInstance = Expression.Parameter(instanceType, "instance");
Expression accessPath = accessInstance;
foreach (var memberAccess in memberAccessPath)
{
if (memberAccess is MethodInfo)
{
var methodInfo = (MethodInfo)memberAccess;
if (methodInfo.IsGetterMethod())
{
accessPath = Expression.Call(accessPath, methodInfo);
}
else
{
accessPath = Expression.Call(accessPath, (MethodInfo)memberAccess, value);
}
}
else
{
accessPath = Expression.MakeMemberAccess(accessPath, memberAccess);
}
}
if (!(accessPath is MethodCallExpression))
{
accessPath = Expression.Assign(accessPath, value);
}
var delegateType = typeof(Action <,>).MakeGenericType(instanceType, valueType);
return(LambdaExpression.Lambda(delegateType, accessPath, accessInstance, value));
}
internal static LambdaExpression GetGetterLambdaExpression(this MemberAccessPath memberAccessPath)
{
var instanceType = memberAccessPath.First().ReflectedType;
var returnType = memberAccessPath.Last().GetMemberType();
var accessInstance = Expression.Parameter(instanceType, "instance");
Expression accessPath = accessInstance;
foreach (var memberAccess in memberAccessPath)
{
if (memberAccess is MethodInfo)
{
accessPath = Expression.Call(accessPath, (MethodInfo)memberAccess);
}
else
{
accessPath = Expression.MakeMemberAccess(accessPath, memberAccess);
}
}
var delegateType = typeof(Func <,>).MakeGenericType(instanceType, returnType);
return(LambdaExpression.Lambda(delegateType, accessPath, accessInstance));
}
internal static LambdaExpression GetSetterExpInstantiateNullInstances(this MemberAccessPath memberAccessPath)
{
var instanceType = memberAccessPath.First().ReflectedType;
var valueType = memberAccessPath.Last().GetMemberType();
var value = Expression.Parameter(valueType, "value");
var entryInstance = Expression.Parameter(instanceType, "instance");
Expression accessPath = entryInstance;
var memberAccesses = new List <Expression>();
foreach (var memberAccess in memberAccessPath)
{
if (memberAccess is MethodInfo methodInfo)
{
if (methodInfo.IsGetterMethod())
{
accessPath = Expression.Call(accessPath, methodInfo);
}
else
{
accessPath = Expression.Call(accessPath, methodInfo, value);
}
}
else
{
accessPath = Expression.MakeMemberAccess(accessPath, memberAccess);
}
memberAccesses.Add(accessPath);
}
if (!(accessPath is MethodCallExpression))
{
accessPath = Expression.Assign(accessPath, value);
}
var nullConstant = Expression.Constant(null);
var nullChecks = memberAccesses.Take(memberAccesses.Count - 1).Select((memberAccess, i) =>
{
if (memberAccessPath[i] is MethodInfo methodInfo)
{
//nested method calls like GetCustomer().SetName() include non-writable member (GetCustomer).
//Assigning a new instance in that case is more difficult.
//In that case 'by convention' we should look for:
// - A property named Customer
// - A method named SetCustomer(argument type = getter return type)
// (also take into account Set, Set_, set, set_) as for convention.
var bindingAttributes = BindingFlags.Instance | BindingFlags.Public
| BindingFlags.FlattenHierarchy | BindingFlags.NonPublic;
string setterMethodName = null;
if (methodInfo.Name.StartsWith("Get"))
{
setterMethodName = methodInfo.Name.Replace("Get", "Set");
}
else if (methodInfo.Name.StartsWith("get"))
{
setterMethodName = methodInfo.Name.Replace("get", "set");
}
else if (methodInfo.Name.StartsWith("Get_"))
{
setterMethodName = methodInfo.Name.Replace("Get_", "Set_");
}
else if (methodInfo.Name.StartsWith("get_"))
{
setterMethodName = methodInfo.Name.Replace("get_", "set_");
}
var setterMethod = methodInfo.ReflectedType.GetMethod(setterMethodName, bindingAttributes);
Expression setterAccessPath = entryInstance;
for (int j = 0; j < i; j++)
{
if (memberAccessPath[j] is MethodInfo mi)
{
if (mi.IsGetterMethod())
{
setterAccessPath = Expression.Call(accessPath, mi);
}
else
{
setterAccessPath = Expression.Call(accessPath, mi, value);
}
}
else
{
setterAccessPath = Expression.MakeMemberAccess(setterAccessPath, memberAccessPath[j]);
}
}
setterAccessPath = Expression.Call(setterAccessPath, setterMethod, Expression.New(memberAccess.Type));
var equalsNull = Expression.Equal(memberAccess, nullConstant);
return((Expression)Expression.IfThen(equalsNull, setterAccessPath));
}
else
{
var createInstance = Expression.Assign(memberAccess, Expression.New(memberAccess.Type));
var equalsNull = Expression.Equal(memberAccess, nullConstant);
return((Expression)Expression.IfThen(equalsNull, createInstance));
}
}).Where(nc => nc != null).ToList();
var exp = Expression.Block
(
nullChecks.Any() ? Expression.Block(nullChecks.ToArray())
: (Expression)Expression.Empty(),
accessPath
);
var delegateType = typeof(Action <,>).MakeGenericType(instanceType, valueType);
return(LambdaExpression.Lambda(delegateType, exp, entryInstance, value));
}
