public void NoParameterTest()
{
Expression <Func <Foo> > foo = () => new Foo();
var attributeData = AttributeUtility.ExpressionToCustomAttributeData(foo.Body);
Assert.AreEqual(typeof(Foo), attributeData.AttributeType);
Assert.AreEqual(0, attributeData.ConstructorArguments.Count);
Assert.AreEqual(0, attributeData.NamedArguments.Count);
}
public void HasParametersTest()
{
Expression <Func <Foo> > foo = () => new Foo(1, 2)
{
i = 10,
array = new [] { 3, 4 },
T = typeof(object),
S = default
};
var attributeData = AttributeUtility.ExpressionToCustomAttributeData(foo.Body);
var constructorArguments = attributeData.ConstructorArguments;
Assert.AreEqual(typeof(Foo), attributeData.AttributeType);
Assert.AreEqual(1, constructorArguments[0].Value);
Assert.AreEqual(2, constructorArguments[1].Value);
for (int i = 0; i < 3; ++i)
{
var namedArgument = attributeData.NamedArguments[i];
var value = namedArgument.TypedValue.Value;
switch (namedArgument.MemberName)
{
case nameof(Foo.i):
Assert.AreEqual(10, value);
break;
case nameof(Foo.array):
CollectionAssert.AreEqual(new[] { 3, 4 }, (int[])value);
break;
case nameof(Foo.T):
Assert.AreEqual(typeof(object), value);
break;
default:
Assert.Fail();
break;
}
}
}
public void ManualExpressionTest()
{
var type = typeof(Foo);
MemberInfo GetFooMember(
string name)
{
const MemberTypes memberTypes = MemberTypes.Property | MemberTypes.Field;
const BindingFlags bindingFlags = BindingFlags.Instance | BindingFlags.Public | BindingFlags.DeclaredOnly;
var member = type.GetMember(name, memberTypes, bindingFlags)[0];
return(member);
}
var expression = Expression.MemberInit(
Expression.New(
type.GetConstructor(new[]
{
typeof(int),
typeof(int),
typeof(int[])
}),
Expression.Constant(1),
Expression.Default(typeof(int)),
Expression.NewArrayInit(
typeof(int),
Expression.Constant(2),
Expression.Constant(3))),
Expression.Bind(
GetFooMember(nameof(Foo.i)),
Expression.Constant(10)),
Expression.Bind(
GetFooMember(nameof(Foo.array)),
Expression.NewArrayInit(
typeof(int),
Expression.Constant(3),
Expression.Constant(4))),
Expression.Bind(
GetFooMember(nameof(Foo.T)),
Expression.Constant(typeof(object))),
Expression.Bind(
GetFooMember(nameof(Foo.S)),
Expression.Default(typeof(string))),
Expression.Bind(
GetFooMember(nameof(Foo.d)),
Expression.Default(typeof(int))));
var attributeData = AttributeUtility.ExpressionToCustomAttributeData(expression);
var constructorArguments = attributeData.ConstructorArguments;
Assert.AreEqual(typeof(Foo), attributeData.AttributeType);
Assert.AreEqual(1, constructorArguments[0].Value);
Assert.AreEqual(0, constructorArguments[1].Value);
CollectionAssert.AreEqual(new[] { 2, 3 }, (int[])constructorArguments[2].Value);
for (int i = 0; i < 5; ++i)
{
var namedArgument = attributeData.NamedArguments[i];
var value = namedArgument.TypedValue.Value;
switch (namedArgument.MemberName)
{
case nameof(Foo.i):
Assert.AreEqual(10, value);
break;
case nameof(Foo.array):
CollectionAssert.AreEqual(new[] { 3, 4 }, (int[])value);
break;
case nameof(Foo.T):
Assert.AreEqual(typeof(object), value);
break;
case nameof(Foo.S):
Assert.IsNull(value);
break;
case nameof(Foo.d):
Assert.AreEqual(0, value);
break;
default:
Assert.Fail();
break;
}
}
}
