Nullable detection kludge

[jon.rea]

Please tell me there is a better way :-D

....

public static bool IsNullableType(Type paramType)
{
return paramType.IsGenericType &&
paramType.GetGenericTypeDefinition() == typeof
(Nullable<>);
}

public static bool IsNullableTypeMatch(Type paramType, Type
argType)
{
return IsNullableType(paramType) &&
argType.IsValueType &&
paramType.FullName.Contains(argType.FullName); //
**********Kludge***********
}

- paramType {Name = "Nullable`1" FullName = "System.Nullable`1
[[System.Int32, mscorlib, Version=2.0.0.0, Culture=neutral,
PublicKeyToken=b77a5c561934e089]]"} System.Type {System.RuntimeType}

- argType {Name = "Int32" FullName = "System.Int32"} System.Type
{System.RuntimeType}

IsNullableTypeMatch(...) -->

Nullable<Int32with Int32 -- returns true
Nullable<OtherValueTypewith Int32 -- returns false
Nullable<Int32with OtherValueType -- returns false

Any ideas how I can remove my kludge???

Many thanks for any help,
Jon

[Hans Kesting]

jo*****@gmail.com submitted this idea :

Please tell me there is a better way :-D

...

public static bool IsNullableType(Type paramType)
{
return paramType.IsGenericType &&
paramType.GetGenericTypeDefinition() == typeof
(Nullable<>);
}

public static bool IsNullableTypeMatch(Type paramType, Type
argType)
{
return IsNullableType(paramType) &&
argType.IsValueType &&
paramType.FullName.Contains(argType.FullName); //
**********Kludge***********
}

- paramType {Name = "Nullable`1" FullName = "System.Nullable`1
[[System.Int32, mscorlib, Version=2.0.0.0, Culture=neutral,
PublicKeyToken=b77a5c561934e089]]"} System.Type {System.RuntimeType}

- argType {Name = "Int32" FullName = "System.Int32"} System.Type
{System.RuntimeType}

IsNullableTypeMatch(...) -->

Nullable<Int32with Int32 -- returns true
Nullable<OtherValueTypewith Int32 -- returns false
Nullable<Int32with OtherValueType -- returns false

Any ideas how I can remove my kludge???

Many thanks for any help,
Jon

This should work:

public static bool IsNullableTypeMatch(Type paramType, Type argType)
{
return IsNullableType(paramType) &&
argType.IsValueType &&
paramType.GetGenericArguments()[0] == argType;
}

Hans Kesting

[Ben Voigt [C++ MVP]]

Hans Kesting wrote:

jo*****@gmail.com submitted this idea :

>Please tell me there is a better way :-D

...

public static bool IsNullableType(Type paramType)
{
return paramType.IsGenericType &&
paramType.GetGenericTypeDefinition() == typeof
(Nullable<>);
}

public static bool IsNullableTypeMatch(Type paramType, Type
argType)
{
return IsNullableType(paramType) &&
argType.IsValueType &&
paramType.FullName.Contains(argType.FullName); //
**********Kludge***********
}

- paramType {Name = "Nullable`1" FullName = "System.Nullable`1
[[System.Int32, mscorlib, Version=2.0.0.0, Culture=neutral,
PublicKeyToken=b77a5c561934e089]]"} System.Type {System.RuntimeType}

- argType {Name = "Int32" FullName = "System.Int32"} System.Type
{System.RuntimeType}

IsNullableTypeMatch(...) -->

Nullable<Int32with Int32 -- returns true
Nullable<OtherValueTypewith Int32 -- returns false
Nullable<Int32with OtherValueType -- returns false

Any ideas how I can remove my kludge???

Many thanks for any help,
Jon

This should work:

public static bool IsNullableTypeMatch(Type paramType, Type argType)
{
return IsNullableType(paramType) &&
argType.IsValueType &&

the IsValueType check here is unnecessary

paramType.GetGenericArguments()[0] == argType;
}

Hans Kesting