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ASP.NET MVC: Custom Validation by DataAnnotation
...ntext validationContext)
{
var properties = this.PropertyNames.Select(validationContext.ObjectType.GetProperty);
var values = properties.Select(p => p.GetValue(validationContext.ObjectInstance, null)).OfType<string>();
var totalLength = values.Sum(x => x.Lengt...
Filtering for empty or NULL names in a queryset
...null, not-empty alias field. The generated SQL would look something like:
SELECT * FROM Name WHERE alias IS NOT NULL AND alias != ""
You can also pass multiple arguments to a single call to exclude, which would ensure that only objects that meet every condition get excluded:
Name.objects.exclude...
How do I remove version tracking from a project cloned from git?
...efer to this article for a visual guide
In the view menu on the toolbar, select Options
In the Advanced Settings section, find Hidden files and Folders under the Files and Folders list and select Show hidden files and folders
Close the options menu and you should see all hidden folders and files ...
How do I display the current value of an Android Preference in the Preference summary?
..., and ListPreference.getSummary() will format the summary with the current selected entry (or "" if none selected).
– SOFe
Aug 3 '16 at 7:19
...
Multiple Indexes vs Multi-Column Indexes
...e multi-column index can be used for queries referencing all the columns:
SELECT *
FROM TableName
WHERE Column1=1 AND Column2=2 AND Column3=3
This can be looked up directly using the multi-column index. On the other hand, at most one of the single-column index can be used (it would have to look u...
mysql create user if not exists
...
I use
SELECT EXISTS (SELECT DISTINCT user FROM mysql.user WHERE user = "username") as is_user
should return 1 if exists or 0 if it does not
share
...
How to change the background color of a UIButton while it's highlighted?
...ged" forState:UIControlStateHighlighted];
[myButton addTarget:self action:@selector(buttonHighlight:) forControlEvents:UIControlEventTouchDown];
[myButton addTarget:self action:@selector(buttonNormal:) forControlEvents:UIControlEventTouchUpInside];
Option 2:
Return an image made from the highligh...
Exception thrown inside catch block - will it be caught again?
...lause of the try statement, then the first (leftmost) such catch clause is selected. The value V is assigned to the parameter of the selected catch clause, and the Block of that catch clause is executed. If that block completes normally, then the try statement completes normally; if that block compl...
“Prevent saving changes that require the table to be re-created” negative effects
...ESCALATION = TABLE)
GO
SET IDENTITY_INSERT raw.Tmp_Contact ON
GO
IF EXISTS(SELECT * FROM raw.Contact)
EXEC('INSERT INTO raw.Tmp_Contact (ContactID, ProfileID, AddressType, ContactText)
SELECT ContactID, ProfileID, AddressType, ContactText FROM raw.Contact WITH (HOLDLOCK TABLOCKX)')
GO
S...
UIButton Long Press Event
...gPress = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(longPress:)];
[self.button addGestureRecognizer:longPress];
[longPress release];
And then implement the method that handles the gesture
- (void)longPress:(UILongPressGestureRecognizer*)gesture {
if ( gesture.s...