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?? Coalesce for empty string?
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There isn't a built-in way to do this. You could make your extension method return a string or null, however, which would allow the coalescing operator to work. This would be odd, however, and I personally prefer your current approach.
Sin...
event.preventDefault() function not working in IE
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in IE, you can use
event.returnValue = false;
to achieve the same result.
And in order not to get an error, you can test for the existence of preventDefault:
if(event.preventDefault) event.preventDefault();
You can combine the two with:
event.preventDefault ? event.preventDefault() : (even...
How can I get my webapp's base URL in ASP.NET MVC?
... Add framework services.
services.AddMvc();
services.AddTransient<MyClass, MyClass>();
services.TryAddSingleton<IHttpContextAccessor, HttpContextAccessor>();
}
then have it injected for you like this:
private HttpContext currentContext;
public MyClass(IHttpContextAccesso...
how to use python to execute a curl command
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curl -d @<file> will read the fields to post from <file> - that's not the same as file upload.
– Lukas Graf
Aug 25 '14 at 17:32
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How to scale a UIImageView proportionally?
...ht;
CGPoint thumbnailPoint = CGPointMake(0.0,0.0);
if (CGSizeEqualToSize(imageSize, targetSize) == NO) {
CGFloat widthFactor = targetWidth / width;
CGFloat heightFactor = targetHeight / height;
if (widthFactor < heightFactor)
scaleFactor = widthFac...
Better way to sum a property value in an array
... function to the Array prototype, I am updating this answer to provide an alternative that keeps the syntax similar to the syntax originally requested in the question.
class TravellerCollection extends Array {
sum(key) {
return this.reduce((a, b) => a + (b[key] || 0), 0);
}
}
con...
Making iTerm to translate 'meta-key' in the same way as in other OSes
...ward on the shell prompt respectively. Usually, the meta key is mapped to Alt key on Windows and Linux. However, in iTerm, I could not find a way to map this meta key to either Option or Command key on my MacBook Pro.
...
Printing everything except the first field with awk
...es a space as Ben Jackson mentioned, so use a for loop:
awk '{for (i=2; i<=NF; i++) print $i}' filename
So if your string was "one two three", the output will be:
two
three
If you want the result in one row, you could do as follows:
awk '{for (i=2; i<NF; i++) printf $i " "; print $NF}' ...
Can I use git diff on untracked files?
...can't git stash while you have an --intent-to-add file pending like this. Although if you need to stash, you just add the new files and then stash them. Or you can use the emulation workaround:
git update-index --add --cacheinfo \
100644 e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 new.txt
(setting u...
Java: recommended solution for deep cloning/copying an instance
... because the Java spec for it creates many problems.
He provides a few alternatives:
Use a factory pattern in place of a constructor:
public static Yum newInstance(Yum yum);
Use a copy constructor:
public Yum(Yum yum);
All of the collection classes in Java support the copy const...