大约有 38,000 项符合查询结果（耗时：0.0518秒） [XML]
What is a NullReferenceException, and how do I fix it?
... or shorter if (a != null) { b = a; }.
The rest of this article goes into more detail and shows mistakes that many programmers often make which can lead to a NullReferenceException.
More Specifically
The runtime throwing a NullReferenceException always means the same thing: you are trying to use a ...
Realistic usage of the C99 'restrict' keyword?
... that to:
memset(p1, 4, 50);
memset(p2, 9, 50);
which is potentially much more efficient as it may be assembly optimized on a decent libc implementation (like glibc): Is it better to use std::memcpy() or std::copy() in terms to performance?
Does GCC really do it?
GCC 5.2.1.Linux x86-64 Ubuntu 15.10...
How do I test a private function or a class that has private methods, fields or inner classes?
...
|
show 14 more comments
653
...
C# version of java's synchronized keyword?
...in older Microsoft compilers it is a lock(this) / lock(Type) - however, in more recent compilers it uses Interlocked updates - so thread-safe without the nasty parts.
This allows more granular usage, and allows use of Monitor.Wait/Monitor.Pulse etc to communicate between threads.
A related blog en...
Why would I want stage before committing in Git?
...
|
show 6 more comments
26
...
What are the differences between json and simplejson Python modules?
...ut since json was added in 2.6, simplejson has the advantage of working on more Python versions (2.4+).
simplejson is also updated more frequently than Python, so if you need (or want) the latest version, it's best to use simplejson itself, if possible.
A good practice, in my opinion, is to use o...
Default implementation for Object.GetHashCode()
... reference equality is perfect. With strings, as you note, one is usually more interested in whether a string containing the same sequence of characters has already been added. That's why string overrides GetHashCode. On the other hand, suppose you want to keep a count of how many times various c...
Use RSA private key to generate public key?
...tracted from the private key file, not calculated. See my answer below for more details.
– golem
Jun 4 '17 at 17:27
|
show 12 more comments
...
Is there a Max function in SQL Server that takes two values like Math.Max in .NET?
...
|
show 4 more comments
483
...
Find and restore a deleted file in a Git repository
.... I delete a file and commit that change. I continue working and make some more commits. Then, I find I need to restore that file.
...