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How do I get a distinct, ordered list of names from a DataTable using LINQ?
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Try out the following:
dataTable.Rows.Cast<DataRow>().select(dr => dr["Name"].ToString()).Distinct().OrderBy(name => name);
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How to initialize/instantiate a custom UIView class with a XIB file in Swift
... the return type is Self rather than UIView, so the caller doesn't need to cast to the view class.
import UIKit
protocol UIViewLoading {}
extension UIView : UIViewLoading {}
extension UIViewLoading where Self : UIView {
// note that this method returns an instance of type `Self`, rather than U...
How do I set a column value to NULL in SQL Server Management Studio?
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Use This:
Update Table Set Column = CAST(NULL As Column Type) where Condition
Like This:
Update News Set Title = CAST(NULL As nvarchar(100)) Where ID = 50
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Reading Excel files from C#
...looked it up on MSDN. Looks like the <T> is just used to attempt to cast the contents in the column to a type. In this example and just casting the data in the columns to strings. If you wanted a double you would need to call double.Parse(x.Field<string>("Cost") or something like that...
Stopping scripters from slamming your website
...at does the design, writes the product descriptions, podcasts, blog posts, and moderates the forums. I work with CSS/HTML and am only barely familiar with other technologies. I work closely with the developers and have talked through all of the answers here (and many other ideas we've had).
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Oracle Differences between NVL and Coalesce
...you can find a difference in the fact that NVL makes an implicit data type casting if the given values are of different types. So for instance, I was getting an error using COALESCE passing it two NULL values (one explicitly set and the other taken from a column in the database, of type NUMBER), tha...
How can I pass a member function where a free function is expected?
...n using a void* interface as they remove the potential for errors due to a cast to the wrong type.
To clarify how to use a function pointer to call a member function, here is an example:
// the function using the function pointers:
void somefunction(void (*fptr)(void*, int, int), void* context) {
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Java - Method name collision in interface implementation
...Something2 ) are expected ? I cannot even expect client code to be able to cast my instance to the appropriate interface , so am I not loosing something by this restriction ? Also note that in this way , when writing classes that actually implement the respective interfaces , we loose the benefit of...
What is the difference between string primitives and String objects in JavaScript?
...(s).prototype.toString.call = [object String].
The auto-boxing behaviour casts s back and forth to its wrapper type as needed, but the standard operations are incredibly fast since you are dealing with a simpler data type. However auto-boxing and Object.prototype.valueOf have different effects.
I...
Convert from List into IEnumerable format
...plements IEnumerable<T>. It means that you do not have to convert or cast anything.
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