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Unique Key constraints for multiple columns in Entity Framework
...
With Entity Framework 6.1, you 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 spec...
Apply multiple functions to multiple groupby columns
...ame, you can use a normal function and supply a custom name to the special __name__ attribute like this:
def max_min(x):
return x.max() - x.min()
max_min.__name__ = 'Max minus Min'
df.groupby('group').agg({'a':['sum', 'max'],
'b':'mean',
'c'...
Function in JavaScript that can be called only once
...
Accordingly to asawyer's response, you only needed to do _.once(foo) or _.once(bar), and the functions themselves don't need to be aware of being ran only once (no need for the noop and no need for the * = noop).
– fableal
Oct 3 '12 at 17:31
...
JavaScript chop/slice/trim off last character in string
...to conditionally remove the last four characters, only if they are exactly _bar:
var re = /_bar$/;
s.replace(re, "");
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How to delete all Annotations on a MKMapView
...me with copy and paste and removing [locs release] and changing mapView to _mapView. I was following a great tutorial for MKDirections here devfright.com/mkdirections-tutorial and wanted to remove the pin after getting directions. I added the code below the last line of that method to the 'clear rou...
Is it a good practice to use an empty URL for a HTML form's action attribute? (action=“”)
...eters then it shouldn't be a problem isn't it? At least I usually use the $_POST array in PHP only when processing forms.
– Calmarius
Mar 20 '15 at 18:45
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Databinding an enum property to a ComboBox in WPF
... Busy
}
At the top of your XAML:
xmlns:my="clr-namespace:namespace_to_enumeration_extension_class
and then...
<ComboBox
ItemsSource="{Binding Source={my:Enumeration {x:Type my:Status}}}"
DisplayMemberPath="Description"
SelectedValue="{Binding CurrentStatus}"
Selec...
Range references instead values
...{
field string
}
func main() {
var array [10]MyType
for idx, _ := range array {
array[idx].field = "foo"
}
for _, e := range array {
fmt.Println(e.field)
fmt.Println("--")
}
}
...
What are deferred objects?
...e".split(" "),
// Create a simple deferred (one callbacks list)
/* Class: _Deferred.
* methods: done, resolve, resolveWith, isResolved
* internal method: cancel
*
* Basically allows you to attach callbacks with the done method.
* Then resolve the deferred action whenever you want with an a...
App Inventor 2 Enhance 拓展:界面增强扩展(颜色渐变、边距、圆角、透明...
...:
when Screen1.Initialize() {
KevinkunEnhance1.SetBgColor(垂直布局_卡片, "#FAFAFA", 0)
KevinkunEnhance1.SetRoundCorner(垂直布局_卡片, 16)
KevinkunEnhance1.SetBorder(垂直布局_卡片, 1, "#DDDDDD")
KevinkunEnhance1.SetPadding(垂直布局_卡片, 16)
KevinkunEnhance1.SetEl...
