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LINQ's Distinct() on a particular property
...unc<TSource, TKey> keySelector)
{
HashSet<TKey> seenKeys = new HashSet<TKey>();
foreach (TSource element in source)
{
if (seenKeys.Add(keySelector(element)))
{
yield return element;
}
}
}
So to find the distinct values using jus...
Gulps gulp.watch not triggered for new or deleted files?
...
Edit: Apparently gulp.watch does work with new or deleted files now. It did not when the question was asked.
The rest of my answer still stands: gulp-watch is usually a better solution because it lets you perform specific actions only on the files that have been mod...
JSON formatter in C#?
...e 3.1
public string PrettyJson(string unPrettyJson)
{
var options = new JsonSerializerOptions(){
WriteIndented = true
};
var jsonElement = JsonSerializer.Deserialize<JsonElement>(unPrettyJson);
return JsonSerializer.Serialize(jsonElement, options);
}
...
What is the difference between Factory and Strategy patterns?
...tingSystem ) {
case UNIX :
case LINUX : return new UnixCommand();
case WINDOWS : return new WindowsCommand();
case OSX : return new OSXCommand();
}
}
But suppose your factory needs more advanced or dynamic creation. You may add to the ...
How do you get a timestamp in JavaScript?
...
Short & Snazzy:
+ new Date()
A unary operator like plus triggers the valueOf method in the Date object and it returns the timestamp (without any alteration).
Details:
On almost all current browsers you can use Date.now() to get the UTC tim...
Android Spinner: Get the selected item change event
...r use OnItemSelectedListener() instead:
spinner.setOnItemSelectedListener(new OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parentView, View selectedItemView, int position, long id) {
// your code here
}
@Override
public void onNot...
UINavigationController without navigation bar?
...d be able to do the following:
self.navigationController.navigationBar.isHidden = true //Swift 5
where self.navigationController is (obviously) an instance of UINavigationController. Seems to work for me, but I only briefly tested it before posting this.
...
Must qualify the allocation with an enclosing instance of type GeoLocation
...cause you're trying to create an instance of an inner class service.submit(new ThreadTask(i));
without creating instance of main class..
To resolve this issue please create instance of main class first:
GeoLocation outer = new GeoLocation();
Then create instance of class you intended to call, as...
How to set SQL Server connection string?
... username and password
using System.Data.SqlClient;
SqlConnection conn = new SqlConnection();
conn.ConnectionString =
"Data Source=ServerName;" +
"Initial Catalog=DataBaseName;" +
"User id=UserName;" +
"Password=Secret;";
conn.Open();
.NET DataProvider -- Trusted Connection
SqlConnectio...
How to set RelativeLayout layout params in code not in xml?
...
Just a basic example:
RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
params.addRule(RelativeLayout.ALIGN_PARENT_LEFT, RelativeLayout.TRUE);
Button button1;
button1.setLayoutPara...