大约有 2,193 项符合查询结果（耗时：0.0092秒） [XML]
How to read a line from the console in C?
...ters it read. So you use fgetc:
char * getline(void) {
char * line = malloc(100), * linep = line;
size_t lenmax = 100, len = lenmax;
int c;
if(line == NULL)
return NULL;
for(;;) {
c = fgetc(stdin);
if(c == EOF)
break;
if(--len == 0)...
How can I programmatically check whether a keyboard is present in iOS app?
...tance;
}
+ (void)load
{
NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
sharedInstance = [[self alloc] init];
[pool release];
}
- (BOOL)isVisible
{
return _isVisible;
}
- (void)didShow
{
_isVisible = YES;
}
- (void)didHide
{
_isVisible = NO;
}
- (id)init
{
...
What's the difference between VARCHAR and CHAR?
...n hold is 255 characters.
It's 50% faster than VARCHAR.
Uses static memory allocation.
VARCHAR
Used to store variable length alphanumeric data.
The maximum this data type can hold is up to
Pre-MySQL 5.0.3: 255 characters.
Post-MySQL 5.0.3: 65,535 characters shared for the row.
It's slower tha...
boost::flat_map and its performance compared to map and unordered_map
... few variations of the scenario.
A container performance is affected by:
Allocator
size of contained type
cost of implementation of copy operation, assignment operation, move operation, construction operation, of the contained type.
number of elements in the container (size of the problem)
type ha...
How to find a Java Memory Leak
...t "TRACE nnnn" to see the top few frames of the stack where the object was allocated. Often, once I see where the object is allocated, I find a bug and I'm done. Also, note that you can control how many frames are recorded in the stack with the options to -Xrunhprof.
If you check out the allocation...
What is a Windows Handle?
... Value;
}
class LargeObj{
char * val;
LargeObj()
{
val = malloc(2048 * 1000);
}
}
void foo(Object bar){
LargeObj lo = new LargeObj();
bar.Value++;
}
void main()
{
Object obj = new Object();
obj.val = 1;
foo(obj);
printf("%d", obj.val);
}
So because obj wa...
How to create local notifications?
...n *)notification {
UIAlertView *notificationAlert = [[UIAlertView alloc] initWithTitle:@"Notification" message:@"This local notification"
delegate:nil cancelButtonTitle:@"Ok" otherButtonTitles:nil, nil];
[notificationAlert show];
// NSLog(@"didReceiveLocalNotific...
Set UILabel line spacing
...his:
NSMutableAttributedString* attrString = [[NSMutableAttributedString alloc] initWithString:@"Sample text"];
NSMutableParagraphStyle *style = [[NSMutableParagraphStyle alloc] init];
[style setLineSpacing:24];
[attrString addAttribute:NSParagraphStyleAttributeName
value:style
range:NSMak...
iOS: Compare two dates
...STimeInterval distance
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:@"dd/MM/yyyy"];
[dateFormatter setLocale:[[[NSLocale alloc] initWithLocaleIdentifier:@"en_US"]
autorelease]];
NSString *stringDate = [dateFormatter stringF...
Is the pImpl idiom really used in practice?
... create a structure for the private objects of a class and dynamically allocate them to decrease the compilation time (and also hide the private implementations in a better manner).
...