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What is the purpose of “return await” in C#?
...int It really doesn't compile. Assuming the return type of SecondAwait is `string, the error message is: "CS4016: Since this is an async method, the return expression must be of type 'string' rather than 'Task<string>'".
– svick
Nov 23 '16 at 12:17
...
Remove blank attributes from an Object in Javascript
... loop through the object:
var test = {
test1 : null,
test2 : 'somestring',
test3 : 3,
}
function clean(obj) {
for (var propName in obj) {
if (obj[propName] === null || obj[propName] === undefined) {
delete obj[propName];
}
}
}
clean(test);
If you're concerned abou...
What does passport.session() middleware do?
...
passport.session() acts as a middleware to alter the req object and change the 'user' value that is currently the session id (from the client cookie) into the true deserialized user object.
Whilst the other answers make some good points I thought that so...
How do I get the path and name of the file that is currently executing?
... this is weird: when running from command line "__file__" in quotes (as string) gives the dir from which cmd is run, but __file__ (without quotes gives the path to the source file ... why is that
– muon
May 9 '18 at 13:53
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Check if a subview is in a view
...
You will end up with a code like :
Objective-C
- (IBAction)showPopup:(id)sender {
if(![self.myView isDescendantOfView:self.view]) {
[self.view addSubview:self.myView];
} else {
[self.myView removeFromSuperview];
}
}
Swift 3
@IBAction func showPopup(sender: AnyObj...
ALTER TABLE to add a composite primary key
I have a table called provider . I have three columns called person , place , thing . There can be duplicate persons, duplicate places, and duplicate things, but there can never be a dupicate person-place-thing combination.
...
Change Image of ImageView programmatically in Android
... @Brave's answer is correct. Using setBackgroundResource() :( did not remove the existing image before using the new image.. so I got two images colliding there. setImageResource() worked tho :). Still .. the post got me on the right track - my thanks for both answers!
...
Avoid passing null as the view root (need to resolve layout parameters on the inflated layout's root
...set the content for the activity, you should be using setContentView(layoutId). If you're trying to add a new view to an existing ViewGroup, you should probably just pass the parent and let the inflater attach the new view.
– Coeffect
Oct 21 '14 at 17:20
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Repeat command automatically in Linux
...
watch also has the unfortunate side effect of clearing the screen, so sometimes the loop is useful. Which to use depends on the desired format of the output.
– William Pursell
Nov 27 '12 at 21:53
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Why is SELECT * considered harmful?
...s especially true when someone adds new columns to underlying tables that didn't exist and weren't needed when the original consumers coded their data access.
Indexing issues. Consider a scenario where you want to tune a query to a high level of performance. If you were to use *, and it returned m...