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The relationship could not be changed because one or more of the foreign-key properties is non-nulla
...
You should delete old child items thisParent.ChildItems one by one manually. Entity Framework doesn't do that for you. It finally cannot decide what you want to do with the old child items - if you want to throw them away or if you want to keep and assign them to other parent entities. You must ...
I want to get the type of a variable at runtime
...that comparison return true, but it would require a few book chapters to really cover TypeTag, so I'll stop here.
Finally, maybe you don't care about the type of the variable at all. Maybe you just want to know what is the class of a value, in which case the answer is rather simple:
val x = 5
x.ge...
Use underscore inside Angular controllers
...derscore, it attaches itself to the window object, and so is available globally.
So you can use it from Angular code as-is.
You can also wrap it up in a service or a factory, if you'd like it to be injected:
var underscore = angular.module('underscore', []);
underscore.factory('_', ['$window', fu...
How to concatenate twice with the C preprocessor and expand a macro as in “arg ## _ ## MACRO”?
...ssing token (see below), is
replaced by the corresponding argument after all macros contained therein have been
expanded. Before being substituted, each argument’s preprocessing tokens are
completely macro replaced as if they formed the rest of the preprocessing file; no other
preprocessin...
Java Reflection: How to get the name of a variable?
...they are in scope.
Perhaps a byte-code engineering library like ASM would allow you to inspect this information at runtime. The only reasonable place I can think of for needing this information is in a development tool, and so byte-code engineering is likely to be useful for other purposes too.
...
Random String Generator Returning Same String [duplicate]
...om instance in the method, which causes it to return the same values when called in quick succession. I would do something like this:
private static Random random = new Random((int)DateTime.Now.Ticks);//thanks to McAden
private string RandomString(int size)
{
StringBuilder builder = new...
How does an underscore in front of a variable in a cocoa objective-c class work?
...to-generated accessor (for the property) knows which ivar to use. Specifically, in your implementation file, your synthesize should look like this:
@synthesize missionName = _missionName;
More generically, this is:
@synthesize propertyName = _ivarName;
...
Check if all elements in a list are identical
... = next(iterator)
except StopIteration:
return True
return all(first == rest for rest in iterator)
One-liner:
def checkEqual2(iterator):
return len(set(iterator)) <= 1
Also one-liner:
def checkEqual3(lst):
return lst[1:] == lst[:-1]
The difference between the 3 versi...
Django MEDIA_URL and MEDIA_ROOT
... answer below; it is a better solution.
– Thane Brimhall
Apr 6 '16 at 14:14
is this in your app or project urls.py?
...
How to make good reproducible pandas examples
...s.
Disclaimer: Writing a good question is HARD.
The Good:
do include small* example DataFrame, either as runnable code:
In [1]: df = pd.DataFrame([[1, 2], [1, 3], [4, 6]], columns=['A', 'B'])
or make it "copy and pasteable" using pd.read_clipboard(sep='\s\s+'), you can format the text for Sta...