大约有 40,000 项符合查询结果（耗时：0.0413秒） [XML]
C#泛型(List)中基类和子类 怎么转换？ - 更多技术 - 清泛网 - 专注C/C++及内核技术
...型(List)中基类和子类 怎么转换？List<ChildClass> childList = ...Foo(List<BaseClass> baseList);需求：把子类列表传入函数Foo，Foo支持所有子类列表。方法一：Foo(ch...List<ChildClass> childList = ...
Foo(List<BaseClass> baseList);
需求：把子类列表传入函数...
Shell script - remove first and last quote (") from a variable
...
@jsears Huh? This specifically trims one from the start if there is one, and one from the end if there is one. If you don't want to remove unless both are present; yes, a single sed regex could be used, or the variable substitution could be wrapped i...
Can I “multiply” a string (in C#)?
...
I don't think it's elegant at all. In python the code to do this is: snip * multiplier (It's not horrible.. but neither is it beautiful).
– demented hedgehog
Jun 2 '15 at 2:56
...
Are Javascript arrays sparse?
...ript arrays are implemented differs from browser to browser, but they generally fall back to a sparse implementation - most likely the same one used for property access of regular objects - if using an actual array would be inefficient.
You'll have to ask someone with more knowledge about specific ...
What is this crazy C++11 syntax ==> struct : bar {} foo {};?
...First, we'll take a bog-standard abstract UDT (User-Defined Type):
struct foo { virtual void f() = 0; }; // normal abstract type
foo obj;
// error: cannot declare variable 'obj' to be of abstract type 'foo'
Let's also recall that we can instantiate the UDT at the same time that we define it:
str...
What is Ruby's double-colon `::`?
...
:: is basically a namespace resolution operator. It allows you to access items in modules, or class-level items in classes. For example, say you had this setup:
module SomeModule
module InnerModule
class MyClass
...
How do I negate a test with regular expressions in a bash script?
...ate a test with Regular Expressions. For example, I would like to conditionally add a path to the PATH variable, if the path is not already there, as in:
...
Twig ternary operator, Shorthand if-then-else
...
You can use shorthand syntax as of Twig 1.12.0
{{ foo ?: 'no' }} is the same as {{ foo ? foo : 'no' }}
{{ foo ? 'yes' }} is the same as {{ foo ? 'yes' : '' }}
share
|
impro...
Scoping in Python 'for' loops
I'm not asking about Python's scoping rules; I understand generally how scoping works in Python for loops. My question is why the design decisions were made in this way. For example (no pun intended):
...
View the change history of a file using Git versioning
... edited Sep 21 '16 at 8:17
Toby Allen
10.4k1010 gold badges6767 silver badges119119 bronze badges
answered Aug 24 '09 at 12:05
...