public static void SetProperty(this IDispatch dispatch, string name, params object[] args)
{
if (args.Length < 1)
{
throw new ArgumentException("Invalid argument count", nameof(args));
}
var dispid = dispatch.GetDispIDForName(name);
using (var argVariantArrayBlock = new CoTaskMemVariantArgsBlock(args))
{
using (var namedArgDispidBlock = new CoTaskMemBlock(sizeof(int)))
{
Marshal.WriteInt32(namedArgDispidBlock.Addr, SpecialDispIDs.PropertyPut);
var dispArgs = new DISPPARAMS {
cArgs = args.Length, rgvarg = argVariantArrayBlock.Addr, cNamedArgs = 1, rgdispidNamedArgs = namedArgDispidBlock.Addr
};
var result = dispatch.Invoke(dispid, ref iid, 0, DispatchFlags.PropertyPut | DispatchFlags.PropertyPutRef, ref dispArgs, IntPtr.Zero, out _, out _);
if (result == HResult.DISP_E_MEMBERNOTFOUND)
{
// VBScript objects can be finicky about property-put dispatch flags
result = dispatch.Invoke(dispid, iid, 0, DispatchFlags.PropertyPut, ref dispArgs, IntPtr.Zero, out _, out _);
if (result == HResult.DISP_E_MEMBERNOTFOUND)
{
result = dispatch.Invoke(dispid, iid, 0, DispatchFlags.PropertyPutRef, ref dispArgs, IntPtr.Zero, out _, out _);
}
}
HResult.Check(result);
}
}
}
public static object GetProperty(this IDispatch dispatch, string name, params object[] args)
{
if (!MiscHelpers.Try(out int dispid, () => dispatch.GetDispIDForName(name)))
{
return(Nonexistent.Value);
}
using (var argVariantArrayBlock = new CoTaskMemVariantArgsBlock(args))
{
using (var resultVariantBlock = new CoTaskMemVariantBlock())
{
var dispArgs = new DISPPARAMS {
cArgs = args.Length, rgvarg = argVariantArrayBlock.Addr, cNamedArgs = 0, rgdispidNamedArgs = IntPtr.Zero
};
HResult.Check(dispatch.Invoke(dispid, ref iid, 0, DispatchFlags.PropertyGet, ref dispArgs, resultVariantBlock.Addr, out _, out _));
return(Marshal.GetObjectForNativeVariant(resultVariantBlock.Addr));
}
}
}
public static object InvokeMethod(this IDispatch dispatch, string name, params object[] args)
{
var dispid = dispatch.GetDispIDForName(name);
if (dispid == SpecialDispIDs.GetEnumerator)
{
return(dispatch.GetProperty(SpecialMemberNames.NewEnum, args));
}
using (var argVariantArrayBlock = new CoTaskMemVariantArgsByRefBlock(args))
{
using (var resultVariantBlock = new CoTaskMemVariantBlock())
{
var dispArgs = new DISPPARAMS {
cArgs = args.Length, rgvarg = argVariantArrayBlock.Addr, cNamedArgs = 0, rgdispidNamedArgs = IntPtr.Zero
};
HResult.Check(dispatch.Invoke(dispid, iid, 0, DispatchFlags.Method, ref dispArgs, resultVariantBlock.Addr, out _, out _));
return(Marshal.GetObjectForNativeVariant(resultVariantBlock.Addr));
}
}
}