大约有 46,000 项符合查询结果（耗时：0.0436秒） [XML]
How can I check if an element exists in the visible DOM?
How do you test an element for existence without the use of the getElementById method?
25 Answers
...
Detect encoding and make everything UTF-8
...
If you apply utf8_encode() to an already UTF-8 string, it will return garbled UTF-8 output.
I made a function that addresses all this issues. It´s called Encoding::toUTF8().
You don't need to know what the encoding of your strings is. It can be Latin1 (ISO 8859-1), Windows-125...
How expensive is RTTI?
I understand that there is a resource hit from using RTTI, but how big is it? Everywhere I've looked just says that "RTTI is expensive," but none of them actually give any benchmarks or quantitative data reguarding memory, processor time, or speed.
...
Why are hexadecimal numbers prefixed with 0x?
...
Short story: The 0 tells the parser it's dealing with a constant (and not an identifier/reserved word). Something is still needed to specify the number base: the x is an arbitrary choice.
Long story: In the 60's, the prevalent programming number systems were d...
How do I find the length of an array?
...f(a)/sizeof(*a)) << std::endl;
This doesn't work on pointers (i.e. it won't work for either of the following):
int *p = new int[7];
std::cout << "Length of array = " << (sizeof(p)/sizeof(*p)) << std::endl;
or:
void func(int *p)
{
std::cout << "Length of array ...
Accessing constructor of an anonymous class
...I have a concrete class Class1 and I am creating an anonymous class out of it.
10 Answers
...
Is memcached a dinosaur in comparison to Redis? [closed]
I have worked quite a bit with memcached the last weeks and just found out about Redis. When I read this part of their readme, I suddenly got a warm, cozy feeling in my stomach:
...
Warning: “format not a string literal and no format arguments”
...think NSLog() likes taking only one argument, which is what you're passing it. Also, it already does the formatting for you. Why not just do this?
NSLog(@"%@ %@, %@",
errorMsgFormat,
error,
[error userInfo]);
Or, since you say errorMsgFormat is a format string with a sin...
Convert string to variable name in JavaScript
...
If it's a global variable then window[variableName]
or in your case window["onlyVideo"] should do the trick.
share
|
improve t...
How to check if a process id (PID) exists
...ess, use
kill -0 $pid
But just as @unwind said, if you're going to kill it anyway, just
kill $pid
or you will have a race condition.
If you want to ignore the text output of kill and do something based on the exit code, you can
if ! kill $pid > /dev/null 2>&1; then
echo "Could ...