Christof,
Yes the assignment works, but it still does not accomplish what is required
8-(.
The parameter to the method I am calling requires a SByte *
The InvokeMethod argument that is forwarded to the class is an object []
Based on the documentation of the InvokeMethod this means the the 0th
entry in the object[] must be of type SByte *.
You can not case a SByte * to an object expicitly.
How can i get the SByte * type in to the object array?
Nicolas gave me a method for constructing a SByte * pointer but I can not
load that into the object[].
The Cannot convert message occurs.
AfterI cast the SByte * to an IntPtr as you suggest, I then load this into
the object[0] and then get its type, it is magically (well not really) is
known as a IntPrt type.
using System;
namespace TestUnsafePtr
{
class TestUnsafePtr
{
[STAThread]
static void Main(string[] args)
{
SByte [] myData = new SByte[2] {(sbyte) 'A', (sbyte) 'B'};
unsafe
{
fixed(SByte * ptrParm = myData)
{
Console.WriteLine("myData type = {0}",myData.GetType());
object [] myArgs = new object[1];
myArgs[0] = (IntPtr) ptrParm;
Console.WriteLine("myArgs[0] type = {0}",myArgs[0].GetType());
} // fixed(SByte * PtrmyData = myData)
} // unsafe
} // static void Main ()
} // class TestUnsafePtr
} // namespace TestUnsafePtr
"Christof Nordiek" wrote:
> Hi Pat,
>
> i didn't test it, but should work.
> myData[0] = (IntPtr)ptr;
>
> Hope that helps.
>
> "Pat Ireland" <(E-Mail Removed)> schrieb im Newsbeitrag
> news:47AC4C49-9353-4FCD-A1E0-(E-Mail Removed)...
> > Hi Nicholas,
> >
> > It has been a long time since we last conversed.
> >
> > I was able to use the unsafe & fixed as you specified, however,
> > I have a problem with the last argument on the InvokeMember for the class.
> >
> > This arguments represents a list of object arguments to be passed in the
> > call to the class method.
> >
> > I am unable to expicitly use the ptr as the last agrument in tha call
> > because that gives an argument mismatch on the InvokeMember.
> >
> > I tried to cast the ptr as an object but get the message:
> > Cannot convert type 'sbyte*' to 'object'.
> >
> > I also tried to create an object array, per the InvokeMember examples, but
> > I
> > am unable to assign the ptr to an element of the object array,
> > specifically:
> >
> > object [] myData = new object [1];
> > myData[0] = ptr;
> >
> > failes with the same Cannot convert message.
> >
> > Suggestions?
> >
> > Pat, MCSD/VB.NET/C#
> >
> >
> >
> > "Nicholas Paldino [.NET/C# MVP]" wrote:
> >
> >> Pat,
> >>
> >> The only way to do this is through unsafe code. The SByte* parameter
> >> can only be used in unsafe code. In order to do this, you would want to
> >> do
> >> this:
> >>
> >> // Need unsafe code. Assume your array is stored in a variable named
> >> array.
> >> unsafe
> >> {
> >> // Get the pointer. This is not boxing, it's unsafe code. The
> >> pointer
> >> has to be
> >> // fixed so it doesn't jump around.
> >> fixed (SByte* arrayPointer = array)
> >> {
> >> // Make the call, passing arrayPointer for the SByte* parameter
> >> here.
> >> }
> >> }
> >>
> >> Hope this helps.
> >>
> >>
> >> --
> >> - Nicholas Paldino [.NET/C# MVP]
> >> - (E-Mail Removed)
> >>
> >> "Pat Ireland" <(E-Mail Removed)> wrote in message
> >> news:A760D0EB-621E-4501-8A89-(E-Mail Removed)...
> >> >I am attempting to pass an SByte [] to another .NET class that expects
> >> >the
> >> > data to be passed as SByte *. I searched around and found the boxing
> >> > can
> >> > be
> >> > used to produce a pointer but I'm not sure if this is appropriate. I am
> >> > using
> >> > the following sequence:
> >> >
> >> > // Load class
> >> > Assembly c = Assembl.LoadFrom("filename ....);
> >> >
> >> > // Get the types
> >> > cTypes = c.GetTypes();
> >> >
> >> > // Get the appropriate type entry
> >> > myType=cTypes[1];
> >> >
> >> > // Get the infos
> >> > pInfos = myType.GetMethods();
> >> >
> >> > // Get the appropriate info entry
> >> > myInfo=pInfos[0];
> >> >
> >> > // Create a class instance
> >> > Object myClass = myType.InvokeMember(null, BindingFlags.CreateInstance
> >> > ...
> >> >
> >> > // Data to pass
> >> > SByte [] myData = new SByte[3] {1,2,3};
> >> >
> >> > // Invoke method
> >> > myType.InvokeMember(myInfo.Name,
> >> > BindingFlags.InvokeMember ...
> >> > null,
> >> > myClass,
> >> > myData);
> >> >
> >> > However this signature does work nor does
> >> >
> >> > Object [] parms = new Object [1];
> >> > parms[0] = myData;
> >> > myType.InvokeMember(.....,parms);
> >> >
> >> > Doing:
> >> >
> >> > ParameterInfo[] parmInfo = myInfo.GetParameters [];
> >> >
> >> > shows that parmInfo[0].ParameterType is SByte*
> >> >
> >> > Now how do I get from my SByte [] is SByte *
> >> >
> >> >
> >> >
> >>
> >>
> >>
>
>
>
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