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How to delete an object by id with entity framework
...
I am using the following code in one of my projects:
using (var _context = new DBContext(new DbContextOptions<DBContext>()))
{
try
{
_context.MyItems.Remove(new MyItem() { MyItemId = id });
await _context.SaveChangesAsync();
}
...
Convert a list of data frames into one data frame
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Use bind_rows() from the dplyr package:
bind_rows(list_of_dataframes, .id = "column_label")
share
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improve this answer
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Move capture in lambda
...e following will be legal code in C++14:
using namespace std;
// a unique_ptr is move-only
auto u = make_unique<some_type>( some, parameters );
// move the unique_ptr into the lambda
go.run( [ u{move(u)} ] { do_something_with( u ); } );
But it is much more general in the sense that cap...
Call a “local” function within module.exports from another function in module.exports?
... a direct answer to the question
– Kermit_ice_tea
Mar 3 '16 at 23:24
8
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Creating an empty bitmap and drawing though canvas in Android
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This is probably simpler than you're thinking:
int w = WIDTH_PX, h = HEIGHT_PX;
Bitmap.Config conf = Bitmap.Config.ARGB_8888; // see other conf types
Bitmap bmp = Bitmap.createBitmap(w, h, conf); // this creates a MUTABLE bitmap
Canvas canvas = new Canvas(bmp);
// ready to draw on t...
When should I write the keyword 'inline' for a function/method?
...hether you ask for it or not.
As an aside to prevent inlining in GCC, use __attribute__(( noinline )), and in Visual Studio, use __declspec(noinline).
Does it matter if an application is multithreaded when one writes 'inline' for a function/method?
Multithreading doesn't affect inlining in any...
How are echo and print different in PHP? [duplicate]
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From:
http://web.archive.org/web/20090221144611/http://faqts.com/knowledge_base/view.phtml/aid/1/fid/40
Speed. There is a difference between the two, but speed-wise it
should be irrelevant which one you use. echo is marginally faster
since it doesn't set a return value if you really want to ge...
SQL Server Regular expressions in T-SQL
...oks Online)
Wildcard Meaning
% Any string of zero or more characters.
_ Any single character.
[ ] Any single character within the specified range
(for example, [a-f]) or set (for example, [abcdef]).
[^] Any single character not within the specified range
(for example, [^a - f]) or s...
How do I write output in same place on the console?
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#kinda like the one above but better :P
from __future__ import print_function
from time import sleep
for i in range(101):
str1="Downloading File FooFile.txt [{}%]".format(i)
back="\b"*len(str1)
print(str1, end="")
sleep(0.1)
print(back, end="")
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How to convert a std::string to const char* or char*?
...hat needs const char* you can use
std::string str;
const char * c = str.c_str();
If you want to get a writable copy, like char *, you can do that with this:
std::string str;
char * writable = new char[str.size() + 1];
std::copy(str.begin(), str.end(), writable);
writable[str.size()] = '\0'; // ...