Re: Unmanaged code(dll) function: int myfunc (char* temp)

Without seeing the code in your C method, there's no way to know what's
wrong.


--
Chris Tacke
OpenNETCF Consulting
Managed Code in the Embedded World
www.opennetcf.com
--


"Murthy" <Murthy@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:C70DC73E-98B2-481B-BABE-03FDCF1C40B3@xxxxxxxxxxxxxxxx
Hi,
Thanks for ur Reply....
I tried StringBuilder it worked, But there is some problem with conversion
i
think.
When i tried to convert it to string as sb.Tostring(), it is giving me
some
junk characters which are not alphanumeric.

Can u tell me what i need to do to convert the stringbuilder sb to some
alphanumeric string.

Murthy.

"<ctacke/>" wrote:

First thing to know is that CE doesn't store strings in a char* type, it
uses UTF16, so they are wchar_t.

If the native DLL will be putting data into that variable, you need to
allocate enough memory for it before the call. The easiest way is with a
StringBuilder.

int myfunc (TCHAR* temp)
{
.....
}

[DllImport("mylib.dll")]
public static extern int myfunc(StringBuilder sb);

void MyCall()
{
StringBuilder sb = new StringBuilder(255);
int ret = myfunc(sb);
}


--
Chris Tacke
OpenNETCF Consulting
Managed Code in the Embedded World
www.opennetcf.com
--


"Murthy" <Murthy@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:5F9D1506-CD19-4390-B633-0BDE53BCC1DA@xxxxxxxxxxxxxxxx
Hi,
I want to do an unmanaged call to an DLL
Unmanaged code(dll) function: int myfunc (char* temp)
Here return int type determines the Success.
After execution of the function temp will contain an value

How to do the unmanaged call to this function from c# and later how to
retrieve the value from temp, which hold a string value.

thanks in Advance,
Murthy






.

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