大约有 40,000 项符合查询结果（耗时：0.0172秒） [XML]
What does the Q_OBJECT macro do? Why do all Qt objects need this macro?
...ual const QMetaObject *metaObject() const; virtual void *qt_metacast(const char *); virtual int qt_metacall(QMetaObject::Call, int, void **); static inline QString tr(const char *s, cons
t char *c = nullptr, int n = -1) { return staticMetaObject.tr(s, c, n); } __attribute__ ((__deprecated__)) static...
How to throw std::exceptions with variable messages?
...ptions can be constructed from a std::string:
#include <stdexcept>
char const * configfile = "hardcode.cfg";
std::string const anotherfile = get_file();
throw std::runtime_error(std::string("Failed: ") + configfile);
throw std::runtime_error("Error: " + anotherfile);
Note that the base cl...
REDHAT 6.4 X64下ORACLE 11GR2静默安装 - 数据库(内核) - 清泛网 - 专注C/C++及内核技术
...
#
# all_langs : All languages
#
# Specify value as the following to select any of the languages.
# Example : SELECTED_LANGUAGES=en,fr,ja
#
# Specify value as the following to select all the languages.
# Example : SELECTED_LANGUAGES=all_langs
#---------------------------------------------...
How do you reverse a string in place in C or C++?
...
@fredsbend, the "ridiculously long" version of the selected answer handles a case which this simple answer doesn't - UTF-8 input. It shows the importance of fully specifying the problem. Besides the question was about code that would work in C as well.
–...
What is the effect of extern “C” in C++?
...o have a certain linkage:
extern "C" void foo(int);
extern "C"
{
void g(char);
int i;
}
If you care about the technicalities, they are listed in section 7.5 of the C++03 standard, here is a brief summary (with emphasis on extern "C"):
extern "C" is a linkage-specification
Every compiler is r...
conditional unique constraint
... CheckActiveCount(
@Id INT
) RETURNS INT AS BEGIN
DECLARE @ret INT;
SELECT @ret = COUNT(*) FROM CheckConstraint WHERE Id = @Id AND RecordStatus = 1;
RETURN @ret;
END;
GO
ALTER TABLE CheckConstraint
ADD CONSTRAINT CheckActiveCountConstraint CHECK (NOT (dbo.CheckActiveCount(Id) > 1 AND...
max value of integer
...numbers as they were unsigned (that is, handling all bits correctly).
The character data type char is 16 bits wide, unsigned, and holds characters using UTF-16 encoding (however, it is possible to assign a char an arbitrary unsigned 16 bit integer that represents an invalid character codepoint)
...
Sqlite: CURRENT_TIMESTAMP is in GMT, not the timezone of the machine
...a unix
timestamp 1092941466, and compensate
for your local timezone.
SELECT datetime(1092941466, 'unixepoch', 'localtime');
That didn't look like it fit my needs, so I tried changing the "datetime" function around a bit, and wound up with this:
select datetime(timestamp, 'localtime')
That...
Export query result to .csv file in SQL Server 2008
...opy the query.
In Object Explorer right-click on the database in question.
Select "Tasks" >> "Export Data..."
Configure your datasource, and click "Next".
Choose "Flat File" or "Microsoft Excel" as destination.
Specify a file path.
If working with a flat file, configure as desired. If working ...
C/C++获取Windows的CPU、内存、硬盘使用率 - C/C++ - 清泛网 - 专注C/C++及内核技术
...icalDriveStrings()函数获取所有驱动器字符串信息长度。
char* DStr = new char[DSLength];//用获取的长度在堆区创建一个c风格的字符串数组
GetLogicalDriveStrings(DSLength, (LPTSTR)DStr);
//通过GetLogicalDriveStrings将字符串信息复制到堆区数...