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Parallel foreach with asynchronous lambda
...is:
var bag = new ConcurrentBag<object>();
var tasks = myCollection.Select(async item =>
{
// some pre stuff
var response = await GetData(item);
bag.Add(response);
// some post stuff
});
await Task.WhenAll(tasks);
var count = bag.Count;
If you need something more complex, check o...
How to get the Android device's primary e-mail address
...T_DIRECTORY),
ProfileQuery.PROJECTION,
// Select only email addresses.
ContactsContract.Contacts.Data.MIMETYPE + " = ?",
new String[]{ContactsContract.CommonDataKinds.Email.CONTENT_ITEM_TYPE},
// Show primary email add...
Sublime Text 2: How to delete blank/empty lines
...
Select the text
Press:
Ctrl + H on PC, or
Command + Alt + F on Mac or
Click Find->Replace.
Make sure you have selected 'regular expression' by pressing:
Alt + R on PC or
Command + Alt + R on Mac or
Click .* in the Find ...
How to list all the available keyspaces in Cassandra?
...keyspace in the system schema using the SQL query
below is the command.
SELECT * FROM system_schema.keyspaces;
Hope this will answer your question...
You can go through the explanation on understanding and creating the keyspaces from below resources.
Documentation:
https://docs.datastax.co...
Declare variable in table valued function
...
There are two flavors of table valued functions. One that is just a select statement and one that can have more rows than just a select statement.
This can not have a variable:
create function Func() returns table
as
return
select 10 as ColName
You have to do like this instead:
create fu...
How to add a separator to a WinForms ContextMenu?
...er. I'm using VS 2012. You can add a separator via the forms designer.
1) Select/Create a MenuStrip.
2) On "Type Here", right mouse.
3) Select "Insert".
4) Select "Separator".
5) Drag the new separator to the text you want it to be above.
Done.
...
How to use PyCharm to debug Scrapy projects
...
As of 2018.1 this became a lot easier. You can now select Module name in your project's Run/Debug Configuration. Set this to scrapy.cmdline and the Working directory to the root dir of the scrapy project (the one with settings.py in it).
Like so:
Now you can add breakpoin...
How to escape apostrophe (') in MySql?
...
Here's an example:
SELECT * FROM pubs WHERE name LIKE "%John's%"
Just use double quotes to enclose the single quote.
If you insist in using single quotes (and the need to escape the character):
SELECT * FROM pubs WHERE name LIKE '%John\'s%'...
Android SDK Manager Not Installing Components
...ning Android Studio as an administrator, by right-clicking on the .exe and selecting "Run As Administrator".
Also, some anti-virus programs have been known to interfere with SDK Manager.
share
|
im...
Facebook Graph API v2.0+ - /me/friends returns empty, or only friends who also use my application
...s form Facebook.
1) Enable our app status live:
Go to the apps page and select your app
https://developers.facebook.com/apps/
Select status in the top right in Dashboard.
Submit privacy policy URL
Select category
Now our app is in Live status.
One step is completed.
2) Submit our app ...