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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();
}
...
Version number comparison in Python
...o for your cmp function:
>>> cmp = lambda x, y: StrictVersion(x).__cmp__(y)
>>> cmp("10.4.10", "10.4.11")
-1
If you want to compare version numbers that are more complex distutils.version.LooseVersion will be more useful, however be sure to only compare the same types.
>>...
What's the difference between a file descriptor and file pointer?
...ture returned by fopen
typedef struct
{
unsigned char *_ptr;
int _cnt;
unsigned char *_base;
unsigned char *_bufendp;
short _flag;
short _file;
int __stdioid;
char *__newbase;
#ifdef _THREAD_SAFE
v...
Xcode/Simulator: How to run older iOS version?
...
To add previous iOS simulator to Xcode 4.2, you need old xcode_3.2.6_and_ios_sdk_4.3.dmg (or similar version) installer file and do as following:
Mount the xcode_3.2.6_and_ios_sdk_4.3.dmg file
Open mounting disk image and choose menu: Go->Go to Folder...
Type /Volumes/Xcode and iOS...
How to delete last item in list?
... then:
#!/usr/bin/env python
# coding: utf-8
from timer import Timer
if __name__ == '__main__':
a, record = None, []
while not a == '':
with Timer() as t: # everything in the block will be timed
a = input('Type: ')
record.append(t.elapsed_s)
# drop the last...
How to open link in new tab on html?
...
Set the 'target' attribute of the link to _blank:
<a href="#" target="_blank" rel="noopener noreferrer">Link</a>
Edit: for other examples, see here: http://www.w3schools.com/tags/att_a_target.asp
(Note: I previously suggested blank instead of _blank beca...
How to call a parent method from child class in javascript?
...cessing the parent constructor's prototype methods is possible through the __proto__ property (I am pretty sure there will be fellow JS coders to complain that it's depreciated) which is depreciated but at the same time discovered that it is actually an essential tool for sub-classing needs (especia...
private[this] vs private
...nt type T occurs in contravariant position in type Option[T] of value value_=
class Holder[+T] (initialValue: Option[T]) {
This error occurs because value is a mutable variable on the covariant type T (+T) which is normally a problem unless marked as private to the instance with private[this...
How do I change the working directory in Python?
... """Context manager for changing the current working directory"""
def __init__(self, newPath):
self.newPath = os.path.expanduser(newPath)
def __enter__(self):
self.savedPath = os.getcwd()
os.chdir(self.newPath)
def __exit__(self, etype, value, traceback):
...
Adding days to a date in Python
...to do:
import datetime
Then you'll have, using datetime.timedelta:
date_1 = datetime.datetime.strptime(start_date, "%m/%d/%y")
end_date = date_1 + datetime.timedelta(days=10)
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