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Programmatically trigger “select file” dialog box
I have a hidden file input element. Is it possible to trigger its select file dialog box from a button's click event?
13 ...
List comprehension in Ruby
..._ARRAY.map{|x| x % 2 == 0 ? x * 3 : nil}.compact
end
end
def test_select_map
1000.times do
TEST_ARRAY.select{|x| x % 2 == 0 }.map{|x| x * 3}
end
end
def test_inject
1000.times do
TEST_ARRAY.inject([]) {|all, x| all << x*3 if x % 2 == 0; all }
end
end...
Can't launch my app in Instruments: At least one target failed to launch
...To change your code signing identity for Xcode 6:
Click on your Project, Select the Target you are Profiling.
Build Settings -> Code Signing -> Code Signing Identity -> Release
Select your iOS developer profile.
Provisioning Profile: Let Xcode pick the correct Provisioning Profile for yo...
Entity Framework - Include Multiple Levels of Properties
...
For EF 6
using System.Data.Entity;
query.Include(x => x.Collection.Select(y => y.Property))
Make sure to add using System.Data.Entity; to get the version of Include that takes in a lambda.
For EF Core
Use the new method ThenInclude
query.Include(x => x.Collection)
.ThenIncl...
Does the join order matter in SQL?
...t matter. The queries will return same results, as long as you change your selects from SELECT * to SELECT a.*, b.*, c.*.
For (LEFT, RIGHT or FULL) OUTER joins, yes, the order matters - and (updated) things are much more complicated.
First, outer joins are not commutative, so a LEFT JOIN b is no...
How to avoid null checking in Java?
...t that it cannot be null, and that's it.
Example:
public String getFirst3Chars(String text) {
return text.subString(0, 3);
}
However, if your method just passes the value on, and the next method passes it on etc. it could get problematic. In that case you may want to check the argument as abov...
Android emulator-5554 offline
...ll search for ports in use starting with 565. Execute: netstat -a -n -o | Select-String ":565"
PS C:\Users\CJBS> netstat -a -n -o | Select-String ":565"
TCP 127.0.0.1:5653 127.0.0.1:5653 ESTABLISHED 5944
TCP 127.0.0.1:5657 127.0.0.1:5657 ESTABL...
What do querySelectorAll and getElementsBy* methods return?
...sByClassName (and similar functions like getElementsByTagName and querySelectorAll ) work the same as getElementById or do they return an array of elements?
...
Is there a standard keyboard shortcut to build the current project in Visual Studio?
...mmand doesn't seem to work in VS2008.
Assign the shortcut to "Build.BuildSelection". If you have a solution with several projects and files open from the various projects, whatever file you are currently editing will define the project that will be built when you use the assigned shortcut for "Bu...
What is the difference between Debug and Release in Visual Studio?
...nfig (debug and release). When publishing, we can publish according to our selection in the publish dialog. But, when running application, despite I select Debug, it uses release config (bacause I set debug config in base and debug config), is that normal?
– Jonathan
...