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Java List.add() UnsupportedOperationException
...to other List implementations that are either immutable or only allow some selected changes.
You can find out about this by reading the documentation of UnsupportedOperationException and List.add(), which documents this to be an "(optional operation)". The precise meaning of this phrase is explaine...
How to set enum to null
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@equiman no need to cast since the type is specified on the left, you are basically duplicating the first part of my answer that is already accepted.
– Rodney S. Foley
Jul 8 '15 at 22:50
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SqlDataAdapter vs SqlDataReader
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If your goal is to get data using a select query on db, and only access this data at different rows, go to rpevious row, etc, then you can use the SQLDatareader and load it into a datatable using dtable.Load(rdr). Then browse up and down within this datatable. ...
Using isKindOfClass with Swift
...nted out in @Kevin's answer, the correct way would be to use optional type cast operator as?. You can read more about it on the section Optional Chaining sub section Downcasting.
Edit 2
As pointed on the other answer by user @KPM, using the is operator is the right way to do it.
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How to avoid overflow in expr. A * B - C * D
...ere's a work-around that only relies on implementation-defined behavior of casting unsigned integer to signed integer. But this can be expected to work on almost every system today.
(long long)((unsigned long long)A * B - (unsigned long long)C * D)
This casts the inputs to unsigned long long wher...
IEnumerable to string [duplicate]
...urer sequence, rather than a cast. Something like Enumerable.Range(65, 26).Select(i => (char)i);, this should avoid the chance for an optimized shortcut.
– Jodrell
Oct 28 '13 at 9:39
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How to call base.base.method()?
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Nevermind, figured it out. Cast to Func<stuff> instead of Action
– Perkins
Sep 1 '18 at 4:14
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How do I make the return type of a method generic?
...e]);
}
Option 2: When you don't want to use fancy methods of conversion - Cast the value to object and then to generic type.
public static T ConfigSetting<T>(string settingName)
{
return (T)(object)ConfigurationManager.AppSettings[settingName];
}
Note - This will throw an error if t...
NumPy or Pandas: Keeping array type as integer while having a NaN value
...s best to work with float series where possible, even when the series is upcast from int to float due to inclusion of NaN values. This enables vectorised NumPy-based calculations where, otherwise, Python-level loops would be processed.
The docs do suggest : "One possibility is to use dtype=object a...
How do you load custom UITableViewCells from Xib files?
...iles, as prototype cells.
If you need to attach a class to them, you can select the cell prototype and add the corresponding class (must be a descendant of UITableViewCell, of course).
Dequeue
And later on, dequeued using (swift 3.0):
override func tableView(tableView: UITableView, cellForRowA...