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Unique Key constraints for multiple columns in Entity Framework
... can now do this:
[Index("IX_FirstAndSecond", 1, IsUnique = true)]
public int FirstColumn { get; set; }
[Index("IX_FirstAndSecond", 2, IsUnique = true)]
public int SecondColumn { get; set; }
The second parameter in the attribute is where you can specify the order of the columns in the index.
Mor...
Is there a built-in method to compare collections?
...lowing expression checks if two dictionaries are equal regardless of their internal order:
dictionary1.OrderBy(kvp => kvp.Key).SequenceEqual(dictionary2.OrderBy(kvp => kvp.Key))
EDIT: As pointed out by Jeppe Stig Nielsen, some object have an IComparer<T> that is incompatible with th...
How to check if all of the following items are in a list?
... and more clearly-named method, set.issubset. Note that you don't need to convert the argument to a set; it'll do that for you if needed.
set(['a', 'b']).issubset(['a', 'b', 'c'])
share
|
improve...
How to change shape color dynamically?
...ur own shapes in Java.
I did this for an iPhone like Page Controler and paint the shapes in Java:
/**
* Builds the active and inactive shapes / drawables for the page control
*/
private void makeShapes() {
activeDrawable = new ShapeDrawable();
inactiveDrawable = new ShapeDrawable();
...
Easy way to concatenate two byte arrays
...a billion times a second - sure, optimize it. Otherwise, readability and maintainability might be the winning considerations.
– vikingsteve
Dec 6 '13 at 15:35
5
...
ObservableCollection Doesn't support AddRange method, so I get notified for each item added, besides
... index.
''' </summary>
Public Sub InsertRange(ByVal index As Integer, ByVal Collection As IEnumerable(Of T))
Dim ce As New NotifyCollectionChangingEventArgs(Of T)(NotifyCollectionChangedAction.Add, Collection)
OnCollectionChanging(ce)
If ce.Cancel Then Exit Sub
...
Overload constructor for Scala's Case Classes?
...rloading constructors isn't special for case classes:
case class Foo(bar: Int, baz: Int) {
def this(bar: Int) = this(bar, 0)
}
new Foo(1, 2)
new Foo(1)
However, you may like to also overload the apply method in the companion object, which is called when you omit new.
object Foo {
def apply(...
Iteration over std::vector: unsigned vs signed index variable
... /* std::cout << value; ... */
Using indices
for(std::vector<int>::size_type i = 0; i != v.size(); i++) {
/* std::cout << v[i]; ... */
}
Using arrays
Using iterators
for(element_type* it = a; it != (a + (sizeof a / sizeof *a)); it++) {
/* std::cout << *it; ...
Detecting when user has dismissed the soft keyboard
...Subclass the EditText and implement:
@Override
public boolean onKeyPreIme(int keyCode, KeyEvent event) {
if (event.getKeyCode() == KeyEvent.KEYCODE_BACK) {
// Do your thing.
return true; // So it is not propagated.
}
return super.dispatchKeyEvent(event);
}
Here is a link on how to ...
Ruby optional parameters
...ameters:
array = [1, 2, 97, 98, 99]
p array.ascii_to_text([32, 126, 1]) # Convert all ASCII values of 32-126 to their chr value otherwise keep it the same (That's what the optional 1 is for)
output: ["1", "2", "a", "b", "c"]
Okay, cool that works as planned. Now let's check and see what happens ...