October 08, 2012
Hi,
I am playing with samples from Petzold's Programming Windows converted by Andrej Mitrovic. Many thanks, Andrej. :-)
My question is about string conversion. There is a function in virtually every sample named "toUTF16z", which if I understand properly, converts string to UTF-16, so that they can be sent to various Windows API functions. But string literals, for example in MessageBox, are fine, no conversion is needed. I don't understand the magic, what is converted, and when?
If some variable was used e.g. "appName.toUTF16z", and not "Error".toUTF16z
October 08, 2012
On 2012-10-08 10:06, Lubos Pintes wrote:
> Hi,
> I am playing with samples from Petzold's Programming Windows converted
> by Andrej Mitrovic. Many thanks, Andrej. :-)
> My question is about string conversion. There is a function in virtually
> every sample named "toUTF16z", which if I understand properly, converts
> string to UTF-16, so that they can be sent to various Windows API
> functions. But string literals, for example in MessageBox, are fine, no
> conversion is needed. I don't understand the magic, what is converted,
> and when?
> If some variable was used e.g. "appName.toUTF16z", and not "Error".toUTF16z

Without looking at the code, this is my guess:

The "toUTF16z" function converts a D string, of any Unicode encoding, to UTF-16 and converts that to a C string. String literals in D have a trailing null character \0 included making them compatible with functions expecting C strings. String variables on the other do not have the trailing null character and therefore needs a conversion.

-- 
/Jacob Carlborg