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Find an item in List by LINQ?
...u don't need LINQ, just use:
int GetItemIndex(string search)
{
return _list == null ? -1 : _list.IndexOf(search);
}
If you are looking for the item itself, try:
string GetItem(string search)
{
return _list == null ? null : _list.FirstOrDefault(s => s.Equals(search));
}
...
Android: upgrading DB version and adding new table
...on't forget your new users!
Don't forget to add
database.execSQL(DATABASE_CREATE_color);
to your onCreate() method as well or newly installed apps will lack the table.
4. How to deal with multiple database changes over time
When you have successive app upgrades, several of which have database...
In Scala, what exactly does 'val a: A = _' (underscore) mean?
What exactly does val a: A = _ initialize a value to? Is this a typed null? Thanks.
2 Answers
...
What is in your Mathematica tool bag? [closed]
...and Sow which mimics/extends the behavior of GatherBy:
SelectEquivalents[x_List,f_:Identity, g_:Identity, h_:(#2&)]:=
Reap[Sow[g[#],{f[#]}]&/@x, _, h][[2]];
This allows me to group lists by any criteria and transform them in the process. The way it works is that a criteria function (f...
use of deleted function std::unique_ptr 编译错误剖析，你可能少了一个st...
use of deleted function std::unique_ptr 编译错误剖析，你可能少了一个std::move编译报错日志如下： usr include c++ 4 7 bits stl_construct h:77:7: error: use of deleted function & 39;std::unique_ptr<_Tp, _Dp>::unique_ptr(const std::unique_p 编译报错日志如下：
/usr/...
How to check if a variable is a dictionary in Python?
...t, defaultdict, or Counter from the collections module:
if isinstance(any_object, dict):
But there are even more flexible options.
Supporting abstractions:
from collections.abc import Mapping
if isinstance(any_object, Mapping):
This allows the user of your code to use their own custom implem...
Python 2.7: Print to File
...If you want to use the print function in Python 2, you have to import from __future__:
from __future__ import print_function
But you can have the same effect without using the function, too:
print >>f1, 'This is a test'
...
Patterns for handling batch operations in REST web services?
...ces/values in the body of the request. e.g., POST /mail/markAsRead, BODY: i_0_id=0&i_0_value=true&i_1_id=1&i_1_value=false&i_2_id=2&i_2_value=true
– Alex
Apr 25 '13 at 14:31
...
Link to all Visual Studio $ variables
... on my machine. Probably not all macros are defined for others (e.g. OCTAVE_EXECUTABLE), but I wanted to err on the side of inclusiveness here.
For example, this is the first time that I see $(Language) (expanding to C++ for this project) being mentioned outside of the IDE.
$(AllowLocalNetworkLoop...
What does `:_*` (colon underscore star) do in Scala?
...to the method with repeated parameters (as denoted with Node* above).
The _* type annotation is covered in "4.6.2 Repeated Parameters" of the SLS.
The last value parameter of a parameter section may be suffixed by “*”, e.g. (..., x:T *). The type of such a repeated parameter inside th...