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Using C# to check if string contains a string in string array
... Linq possibly have over Array.IndexOf??
– Heckflosse_230
Nov 6 '13 at 20:19
21
This doesn't solv...
Entity Framework: There is already an open DataReader associated with this Command
...ng to iterate is kind of lazy loading (IQueriable).
foreach (var user in _dbContext.Users)
{
}
Converting the IQueriable collection into other enumerable collection will solve this problem.
example
_dbContext.Users.ToList()
Note: .ToList() creates a new set every-time and it can cause th...
When should I use Struct vs. OpenStruct?
...nStruct
Running similar code as burtlo's, on Ruby 1.9.2, (1 of 4 cores x86_64, 8GB RAM) [table edited to align columns]:
creating 1 Mio Structs : 1.43 sec , 219 MB / 90MB (virt/res)
creating 1 Mio Class instances : 1.43 sec , 219 MB / 90MB (virt/res)
creating 1 Mio Hashes : 4...
How to use putExtra() and getExtra() for string data
...een.this, SecondScreen.class);
String strName = null;
i.putExtra("STRING_I_NEED", strName);
Then, to retrieve the value try something like:
String newString;
if (savedInstanceState == null) {
Bundle extras = getIntent().getExtras();
if(extras == null) {
newString= null;
} e...
E11000 duplicate key error index in mongodb mongoose
...xes
From comments:
Your error says that the key is named mydb.users.$email_1 which makes me suspect that you have an index on both users.email and users.local.email (The former being old and unused at the moment). Removing a field from a Mongoose model doesn't affect the database. Check with mydb.u...
unix - head AND tail of file
... 10; my @buf = (); while (<>) { print if $. <= $size; push(@buf, $_); if ( @buf > $size ) { shift(@buf); } } print "------\n"; print @buf;'
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...
ExpandableListView - hide indicator for groups with no children
... states.
When the group has no children, the corresponding state is 'state_empty'
See these reference links:
this and this
For state_empty, you can set a different image which is not confusing, or, simply use transparent color to display nothing...
Add this item in your stateful drawable along ...
Convert NSDate to NSString
...less ARC is active
[formatter release];
Swift 4.2 :
func stringFromDate(_ date: Date) -> String {
let formatter = DateFormatter()
formatter.dateFormat = "dd MMM yyyy HH:mm" //yyyy
return formatter.string(from: date)
}
...
Test whether a list contains a specific value in Clojure
...been the most important function for collections. en.wikipedia.org/wiki/Set_(mathematics)#Membership
– jgomo3
Apr 3 '18 at 11:52
...
How do I read an attribute on a class at runtime?
...fo) As TAttribute
Return info.GetCustomAttributes(GetType(TAttribute), _
False).FirstOrDefault()
End Function
' Example usage over PropertyInfo
Dim fieldAttr = GetAttribute(Of DataObjectFieldAttribute)(pInfo)
If fieldAttr IsNot Nothing AndAlso fieldAttr.Prima...