大约有 41,000 项符合查询结果（耗时：0.0298秒） [XML]
How can I pad a String in Java?
...
What if you need to lpad with other chars (not spaces) ? Is it still possible with String.format ? I am not able to make it work...
– Guido
Aug 11 '09 at 15:48
...
How to compare dates in datetime fields in Postgresql?
... manipulation on the input string, correct? you don't need to be afraid:
SELECT *
FROM table
WHERE update_date >= '2013-05-03'::date
AND update_date < ('2013-05-03'::date + '1 day'::interval);
share
|
...
#define macro for debug printing in C?
...
#include <stdarg.h>
#include <stdio.h>
void dbg_printf(const char *fmt, ...)
{
va_list args;
va_start(args, fmt);
vfprintf(stderr, fmt, args);
va_end(args);
}
You can also use this technique in C99, of course, but the __VA_ARGS__ technique is neater because it uses re...
scanf() leaves the new line char in the buffer
...ing whitespace automatically before trying to parse conversions other than characters. The character formats (primarily %c; also scan sets %[…] — and %n) are the exception; they don't skip whitespace.
Use " %c" with a leading blank to skip optional white space. Do not use a trailing blank in ...
How to send a simple string between two programs using pipes?
...lt;sys/types.h>
#include <unistd.h>
int main()
{
int fd;
char * myfifo = "/tmp/myfifo";
/* create the FIFO (named pipe) */
mkfifo(myfifo, 0666);
/* write "Hi" to the FIFO */
fd = open(myfifo, O_WRONLY);
write(fd, "Hi", sizeof("Hi"));
close(fd);
/* rem...
What is the difference between printf() and puts() in C?
...e (except for the added newline) if the string doesn't contain any control characters (%) but if you cannot rely on that (if mystr is a variable instead of a literal) you should not use it.
So, it's generally dangerous -and conceptually wrong- to pass a dynamic string as single argument of printf...
Maximum length for MySQL type text
...e to the max length of a text field in my MySQL database table. How many characters can a type text field store?
8 Answer...
What are the mechanics of short string optimization in libc++?
...th:
1 bit goes to the long/short flag.
7 bits goes to the size.
Assuming char, 1 byte goes to the trailing null (libc++ will always store a trailing null behind the data).
This leaves 3 words minus 2 bytes to store a short string (i.e. largest capacity() without an allocation).
On a 32 bit mach...
Passing variable arguments to another function that accepts a variable argument list
...#include <stdio.h>
template<typename... Args> void test(const char * f, Args... args) {
printf(f, args...);
}
int main()
{
int a = 2;
test("%s\n", "test");
test("%s %d %d %p\n", "second test", 2, a, &a);
}
At the very least, it works with g++.
...
Why does appending “” to a String save memory?
...s that substring() gives a window onto an existing String - or rather, the character array underlying the original String. Hence it will consume the same memory as the original String. This can be advantageous in some circumstances, but problematic if you want to get a substring and dispose of the o...