大约有 46,000 项符合查询结果（耗时：0.0578秒） [XML]
Co-variant array conversion from x to y may cause run-time exception
...
What it means is this
Control[] controls = new LinkLabel[10]; // compile time legal
controls[0] = new TextBox(); // compile time legal, runtime exception
And in more general terms
string[] array = new string[10];
object[] obj...
Determine what attributes were changed in Rails after_save callback?
...f (self.published_changed? && self.published == true)
end
end
It just works.
share
|
improve this answer
|
follow
|
...
Python concatenate text files
...list of 20 file names, like ['file1.txt', 'file2.txt', ...] . I want to write a Python script to concatenate these files into a new file. I could open each file by f = open(...) , read line by line by calling f.readline() , and write each line into that new file. It doesn't seem very "elegant" to...
How can I restore the MySQL root user’s full privileges?
... removed some of the privileges from my MySQL root user, including the ability to alter tables. Is there some way I can restore this user to its original state (with all privileges)?
...
Determine if code is running as part of a unit test
I have a unit test (nUnit). Many layers down the call stack a method will fail if it is running via a unit test.
19 Answers...
Simpler way to create dictionary of separate variables?
... as a string but I don't know if Python has that much introspection capabilities. Something like:
27 Answers
...
Advantages to Using Private Static Methods
...age on this:
After you mark the methods as static, the compiler will emit non-virtual call sites to these members. Emitting non-virtual call sites will prevent a check at runtime for each call that ensures that the current object pointer is non-null. This can result in a measurable performance g...
What is `related_name` used for in Django?
...lated_name, Django automatically creates one using the name of your model with the suffix _set, for instance User.map_set.all().
If you do specify, e.g. related_name=maps on the User model, User.map_set will still work, but the User.maps. syntax is obviously a bit cleaner and less clunky; so for e...
Getting multiple keys of specified value of a generic Dictionary?
It's easy to get the value of a key from a .NET generic Dictionary:
15 Answers
15
...
Make the current commit the only (initial) commit in a Git repository?
I currently have a local Git repository, which I push to a Github repository.
15 Answers
...