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When to use .First and when to use .FirstOrDefault with LINQ?
... @driis - I'd imagine we can use the mantra of the exceptional exception guideline when choosing between First and FirstOrDefault. Thanks for the clear answer.
– Metro Smurf
Jun 21 '09 at 21:21
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How to pull a random record using Django's ORM?
...anager):
def random(self):
count = self.aggregate(count=Count('id'))['count']
random_index = randint(0, count - 1)
return self.all()[random_index]
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Are there conventions on how to name resources?
Are there conventions how to name resources in Android? For example, buttons, textViews, menus, etc.
15 Answers
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Check if PHP session has already started
...en/function.session-status.php
For versions of PHP < 5.4.0
if(session_id() == '') {
session_start();
}
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How can I get last characters of a string
...avascript string method .substr() combined with the .length property.
var id = "ctl03_Tabs1";
var lastFive = id.substr(id.length - 5); // => "Tabs1"
var lastChar = id.substr(id.length - 1); // => "1"
This gets the characters starting at id.length - 5 and, since the second argument for .subs...
Do AJAX requests retain PHP Session info?
If I had a user logged onto my site, having his id stored in $_SESSION , and from his browser he clicked a 'Save' button which would make an AJAX request to the server. Will his $_SESSION and cookies be retained in this request, and can I safely rely on the id being present in the $_SESSION ?
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Android custom dropdown/popup menu
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Update: To create a popup menu in android with Kotlin refer my answer here.
To create a popup menu in android with Java:
Create a layout file activity_main.xml under res/layout directory which contains only one button.
Filename: activity_main.xml
<RelativeL...
How to set radio button checked as default in radiogroup?
...hould check the radiobutton in the radiogroup like this:
radiogroup.check(IdOfYourButton)
Of course you first have to set an Id to your radiobuttons
EDIT: i forgot, radioButton.getId() works as well, thx Ramesh
EDIT2:
android:checkedButton="@+id/my_radiobtn"
works in radiogroup xml
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How to get last inserted id?
...ine, split for clarity here) to this
INSERT INTO aspnet_GameProfiles(UserId,GameId)
OUTPUT INSERTED.ID
VALUES(@UserId, @GameId)
For SQL Server 2000, or if there is an insert trigger:
INSERT INTO aspnet_GameProfiles(UserId,GameId)
VALUES(@UserId, @GameId);
SELECT SCOPE_IDENTITY()
And then
I...
CASCADE DELETE just once
...cascade.
DELETE FROM some_child_table WHERE some_fk_field IN (SELECT some_id FROM some_Table);
DELETE FROM some_table;
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