大约有 43,000 项符合查询结果（耗时：0.0327秒） [XML]
Escape double quotes in parameter
...ve all the quotes here and place the parameter value in a string used in a select query filter? Can someone help?
– SFDC_Learner
Nov 24 '15 at 16:21
...
Polymorphism in C++
...egorise them in various ways:
When is the polymorphic type-specific code selected?
Run time means the compiler must generate code for all the types the program might handle while running, and at run-time the correct code is selected (virtual dispatch)
Compile time means the choice of type-specif...
Check if a string contains another string
...ontains a ","(comma) in it. Do we have any other option other than reading char-by-char?
4 Answers
...
Replacing a 32-bit loop counter with 64-bit introduces crazy performance deviations with _mm_popcnt_
...;
#include <chrono>
#include <x86intrin.h>
int main(int argc, char* argv[]) {
using namespace std;
uint64_t size=1<<20;
uint64_t* buffer = new uint64_t[size/8];
char* charbuffer=reinterpret_cast<char*>(buffer);
for (unsigned i=0;i<size;++i) charbuffer[i]=...
What's the best way to check if a file exists in C?
...t; // stat
#include <stdbool.h> // bool type
bool file_exists (char *filename) {
struct stat buffer;
return (stat (filename, &buffer) == 0);
}
and call it like this:
#include <stdio.h> // printf
int main(int ac, char **av) {
if (ac != 2)
return 1;
...
Java: splitting a comma-separated string but ignoring commas in quotes
...\"comma: ,\"", all you need to do is strip off the extraneous double quote characters.
– Paul Hanbury
Nov 18 '09 at 17:41
...
What is the purpose of std::make_pair vs the constructor of std::pair?
...two = make_pair (10.5,'A'); // ok: implicit conversion from pair<double,char>
Aside from the implicit conversion bonus of it, if you didn't use make_pair you'd have to do
one = pair<int,int>(10,20)
every time you assigned to one, which would be annoying over time...
...
Platform independent size_t Format specifiers in c?
...
Yes: use the z length modifier:
size_t size = sizeof(char);
printf("the size is %zu\n", size); // decimal size_t ("u" for unsigned)
printf("the size is %zx\n", size); // hex size_t
The other length modifiers that are available are hh (for char), h (for short), l (for long),...
Why is it impossible to build a compiler that can determine if a C++ function will change the value
... /* modify variable */
variable = 1;
}
}
int main(int argc, char **argv) {
if (modifies_variable(f, variable)) {
printf("Modifies variable\n");
} else {
printf("Does not modify variable\n");
}
return 0;
}
...
Reading large text files with streams in C#
...to memory, loads faster as it doesn't make a new string every time you add chars)
– Joshua G
Jan 20 '16 at 15:01
...