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When to use .First and when to use .FirstOrDefault with LINQ?
I've searched around and haven't really found a clear answer as to when you'd want to use .First and when you'd want to use .FirstOrDefault with LINQ.
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Best way to test SQL queries [closed]
...rrors. Essentially this results in sending mail to the incorrect customers and other 'problems' like that.
4 Answers
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How set maximum date in datepicker dialog in android?
... setting the setMaxDate of datePicker the setMaxDate is always highlighted and selected, here is the image
– hasnain_ahmad
Jun 15 '17 at 4:41
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Count number of occurrences of a pattern in a file (even on same line)
...occurrences, use -o. Try this:
echo afoobarfoobar | grep -o foo | wc -l
And man grep of course (:
Update
Some suggest to use just grep -co foo instead of grep -o foo | wc -l.
Don't.
This shortcut won't work in all cases. Man page says:
-c print a count of matching lines
Difference in these...
HashSet vs LinkedHashSet
...), 11), .75f, true); // <-- boolean dummy argument
addAll(c);
}
And (one example of) a HashSet constructor that takes a boolean argument is described, and looks like this:
/**
* Constructs a new, empty linked hash set. (This package private
* constructor is only used by LinkedHashSet....
Add an already existing directory to a directory in Solution Explorer
...irectory in Solution Explorer, but whenever I right-click on the directory and select Add => Existing Item , I can only add individual files, but not directories.
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Extracting just Month and Year separately from Pandas Datetime column
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If you want new columns showing year and month separately you can do this:
df['year'] = pd.DatetimeIndex(df['ArrivalDate']).year
df['month'] = pd.DatetimeIndex(df['ArrivalDate']).month
or...
df['year'] = df['ArrivalDate'].dt.year
df['month'] = df['ArrivalDat...
What are the key differences between Scala and Groovy? [closed]
On the surface Groovy and Scala look pretty similar, aside from Scala being statically typed, and Groovy dynamic.
6 Answers...
jQuery Validate Required Select
...ers: Where is says SelectName it does mean the value of the name attribute and not the value of the id attribute. This is a bit confusing since when working in JS one usually works with the id and not the name. See documentation here: "rules (default: rules are read from markup (classes, attributes,...
How to send a custom http status message in node / express?
... is the correct way to set the statusMessage to something other than the standard message mapped to the StatusCode
– peteb
May 13 '16 at 18:38
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