大约有 22,000 项符合查询结果（耗时：0.0221秒） [XML]
When should static_cast, dynamic_cast, const_cast and reinterpret_cast be used?
...ventData is a structure e.g.
// typedef struct _EventData {
// std::string id;
// std:: string remote_id;
// } EventData;
// On Some Situation a void pointer *pData
// has been static_casted as
// EventData* pointer
EventData *evtdata = static_cast<EventData*>(pData);
...
“PKIX path building failed” and “unable to find valid certification path to requested target”
... certificates.
*/
public class InstallCert {
public static void main(String[] args) throws Exception {
String host;
int port;
char[] passphrase;
if ((args.length == 1) || (args.length == 2)) {
String[] c = args[0].split(":");
host = c[0];...
Why do we need C Unions?
... Here is a trivial example:
typedef union
{
struct {
unsigned char byte1;
unsigned char byte2;
unsigned char byte3;
unsigned char byte4;
} bytes;
unsigned int dword;
} HW_Register;
HW_Register reg;
Then you can access the reg as follows:
reg.dword = 0x...
How to remove all line breaks from a string
...match all variants is
/\r?\n|\r/
If you want to match all newlines in a string, use a global match,
/\r?\n|\r/g
respectively. Then proceed with the replace method as suggested in several other answers. (Probably you do not want to remove the newlines, but replace them with other whitespace, f...
Difference: std::runtime_error vs std::exception()
...
std::runtime_error on the other hand has valid constructors that accept a string as a message. When what() is called a const char pointer is returned that points at a C string that has the same string as was passed into the constructor.
try
{
if (badThingHappened)
{
throw std::run...
The entity type is not part of the model for the current context
...have a number of reasons. In my case, it was the following: The connection string (in Web.config) generated by the .edmx was invalid. After almost a day of trying everything, I changed the connection string from the EF string to an ADO.NET string. This solved my issue.
For example, the EF string lo...
sizeof single struct member in C
...->member)
and use it like this:
typedef struct
{
float calc;
char text[255];
int used;
} Parent;
typedef struct
{
char flag;
char text[member_size(Parent, text)];
int used;
} Child;
I'm actually a bit surprised that sizeof((type *)0)->member) is even allowed as a ...
Identify if a string is a number
If I have these strings:
25 Answers
25
...
How to send emails from my Android application?
...N_SEND);
i.setType("message/rfc822");
i.putExtra(Intent.EXTRA_EMAIL , new String[]{"recipient@example.com"});
i.putExtra(Intent.EXTRA_SUBJECT, "subject of email");
i.putExtra(Intent.EXTRA_TEXT , "body of email");
try {
startActivity(Intent.createChooser(i, "Send mail..."));
} catch (android.c...
What is the email subject length limit?
...56 is any better than 250, or 300, or 372. We're long past using bytes for string lengths.
– Greg Hewgill
Oct 20 '09 at 3:46
4
...