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in a “using” block is a SqlConnection closed on return or exception?
...
Here is my Template. Everything you need to select data from an SQL server. Connection is closed and disposed and errors in connection and execution are caught.
string connString = System.Configuration.ConfigurationManager.ConnectionStrings["CompanyServer"].Connection...
How to determine an object's class?
... are still more methods: Class.isAssignableFrom() and simply attempting to cast the object (which might throw a ClassCastException).
Possible ways summarized
Let's summarize the possible ways to test if an object obj is an instance of type C:
// Method #1
if (obj instanceof C)
;
// Method #2...
How do I return rows with a specific value first?
...to treat boolean expressions as having a numeric value, then you can use:
SELECT *
FROM `Users`
ORDER BY (`city` = 'New York') DESC, `city`
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Why covariance and contravariance do not support value type
... collection of three elements, each being a reference to a string. You can cast this to a collection of objects:
IEnumerable<object> objects = (IEnumerable<object>) strings;
Basically it is the same representation except now the references are object references:
[0] : object referen...
Strange behavior for Map, parseInt [duplicate]
...sort of. You may use [...].map(parseFloat) or [...].map(Number). Both will cast strings to numbers in the given array. However parseFloat and Number work slightly different than parseInt: both will cast floats as well as integers, while Number will turn strings that start with digits and have other ...
How can I convert JSON to a HashMap using Gson?
I'm requesting data from a server which returns data in the JSON format. Casting a HashMap into JSON when making the request wasn't hard at all but the other way seems to be a little tricky. The JSON response looks like this:
...
constant pointer vs pointer on a constant value [duplicate]
...is constant and immutable but the pointed data is not.
You could use const_cast(in C++) or c-style cast to cast away the constness in this case as data itself is not constant.
const char * a;
means that the pointed data cannot be written to using the pointer a.
Using a const_cast(C++) or c-style ...
What is the difference between a strongly typed language and a statically typed language?
...ecause any pointer type is convertible to any other pointer type simply by casting. Pascal was intended to be strongly typed, but an oversight in the design (untagged variant records) introduced a loophole into the type system, so technically it is weakly typed.
Examples of truly strongly typed lan...
“’” showing on page instead of “ ' ”
...tion is wrong. You can also force your web browser to twingle the page by selecting windows-1252 encoding for a utf-8 document. Your web browser cannot detwingle the document that Charlie saved.
Note: the same problem can happen with any other single-byte code page (e.g. latin-1) instead of windo...
How to enumerate an enum with String type?
...ateEnum<T: Hashable>(_: T.Type) -> GeneratorOf<T> {
var cast: (Int -> T)!
switch sizeof(T) {
case 0: return GeneratorOf(GeneratorOfOne(unsafeBitCast((), T.self)))
case 1: cast = { unsafeBitCast(UInt8(truncatingBitPattern: $0), T.self) }
case 2: cast ...