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The type 'string' must be a non-nullable type in order to use it as parameter T in the generic type
...simplify your code by using auto-implemented properties:
public class WordAndMeaning
{
public string Word { get; set; }
public string Meaning { get; set; }
}
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MongoDB: How to query for records where field is null or not set?
...not set then:
db.emails.count({sent_at: {$exists: false}})
If its there and null, or not there at all:
db.emails.count({sent_at: null})
Refer here for querying and null
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Error “initializer element is not constant” when trying to initialize variable with const
...n error on line 6 (initialize my_foo to foo_init) of the following program and I'm not sure I understand why.
5 Answers
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How to detect Safari, Chrome, IE, Firefox and Opera browser?
I have 5 addons/extensions for FF, Chrome, IE, Opera, and Safari.
24 Answers
24
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How to change position of Toast in Android?
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From the documentation,
Positioning your Toast
A standard toast notification appears near the bottom of the screen,
centered horizontally. You can change this position with the
setGravity(int, int, int) method. This accepts three parameters: a
Gravity constant, an x-pos...
how to create a Java Date object of midnight today and midnight tomorrow?
...
Calendar date = new GregorianCalendar();
// reset hour, minutes, seconds and millis
date.set(Calendar.HOUR_OF_DAY, 0);
date.set(Calendar.MINUTE, 0);
date.set(Calendar.SECOND, 0);
date.set(Calendar.MILLISECOND, 0);
// next day
date.add(Calendar.DAY_OF_MONTH, 1);
JDK 8 - java.time.LocalTime and...
npm failed to install time with make not found error
... This solved the issue because the program 'make' es missing and the build-essential package installs it along with several other build tools like g++ which is needed to compile node if you want to go that route. This should be marked as the answer, at least for the OS which is not me...
Why should I prefer single 'await Task.WhenAll' over multiple awaits?
In case I do not care about the order of task completion and just need them all to complete, should I still use await Task.WhenAll instead of multiple await ? e.g, is DoWork2 below a preferred method to DoWork1 (and why?):
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Difference between a Factory, Provider and a Service?
What is the difference between the terms Factory, Provider and Service?
1 Answer
1
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Arrays, heap and stack and value types
...m what I've read on CLR via c#, the answer is yes. But what I can't understand, is what happens to the actual int's inside the array. As they are value types, I'd guess they'd have to be boxed, as I can, for example, pass myIntegers to other parts of the program and it'd clutter up the stack if they...