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Should the hash code of null always be zero, in .NET
...n when object's identifier is null?
The "Remarks" of this MSDN entry goes into more detail around the hash code. Poignantly, the documentation does not provide any coverage or discussion of null values at all - not even in the community content.
To address your issue with the enum, either re-imple...
What is the difference between the states selected, checked and activated in Android?
...
The difference between Checked and Activated is actually quite interesting. Even the Google documentation is apologetic (emphasis below added):
... For example, in a list view with single or multiple selection
enabled, the views in the current selection set are activated. (Um,
y...
The type 'string' must be a non-nullable type in order to use it as parameter T in the generic type
...le<T> type requires that T is a non-nullable value type, for example int or DateTime. Reference types like string can already be null. There would be no point in allowing things like Nullable<string> so it is disallowed.
Also if you are using C# 3.0 or later you can simplify your code b...
How to hide first section header in UITableView (grouped style)
...- (CGFloat) tableView:(UITableView *)tableView heightForHeaderInSection:(NSInteger)section
{
if (section == 0)
return 1.0f;
return 32.0f;
}
- (NSString*) tableView:(UITableView *) tableView titleForHeaderInSection:(NSInteger)section
{
if (section == 0) {
return nil;
...
What is the difference between an interface and abstract class?
What exactly is the difference between an interface and abstract class?
37 Answers
37
...
How do I measure time elapsed in Java? [duplicate]
...- starts;
}
public long time(TimeUnit unit) {
return unit.convert(time(), TimeUnit.MILLISECONDS);
}
}
Usage:
TimeWatch watch = TimeWatch.start();
// do something
long passedTimeInMs = watch.time();
long passedTimeInSeconds = watch.time(TimeUnit.SECONDS);
Aft...
Remove duplicates in the list using linq
...ode == y.Code &&
x.Price == y.Price;
}
public int GetHashCode(Item obj) {
return obj.Id.GetHashCode() ^
obj.Name.GetHashCode() ^
obj.Code.GetHashCode() ^
obj.Price.GetHashCode();
}
}
Then use it like this:
var distinctIt...
How come a non-const reference cannot bind to a temporary object?
...on getx() returns? Clearly, this is prohibited by C++ Standard
but I am interested in the purpose of such restriction, not a reference to the standard.
...
Easy way to write contents of a Java InputStream to an OutputStream
...e the input and/or output stream is asynchronously closed, or
the thread interrupted during the transfer, is highly input and output
stream specific, and therefore not specified
So in order to write contents of a Java InputStream to an OutputStream, you can write:
input.transferTo(output);
...
How do I check if a string is valid JSON in Python?
... #prints True
print is_json('{"foo":[5,6.8],"foo":"bar"}') #prints True
Convert a JSON string to a Python dictionary:
import json
mydict = json.loads('{"foo":"bar"}')
print(mydict['foo']) #prints bar
mylist = json.loads("[5,6,7]")
print(mylist)
[5, 6, 7]
Convert a python object to JSON str...