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Why do we need boxing and unboxing in C#?
...ble)o;
First we have to explicitly unbox the double ((double)o) and then cast that to an int.
What is the result of the following:
double e = 2.718281828459045;
double d = e;
object o1 = d;
object o2 = e;
Console.WriteLine(d == e);
Console.WriteLine(o1 == o2);
Think about it for a second befor...
How to return a 200 HTTP Status Code from ASP.NET MVC 3 controller
...
@MEMark, I had to cast to make it work. Using .NET 4 & MVC 3 I was not provided with an override that would take an HttpStatusCode.
– Shawn South
Feb 25 '14 at 1:26
...
Postgres manually alter sequence
...But if you feed typed variables to the function you may need explicit type casts to satisfy function type resolution. Like:
SELECT setval(my_text_variable::regclass, my_other_variable::bigint, FALSE);
For repeated operations you might be interested in:
ALTER SEQUENCE payments_id_seq START WITH...
Program only crashes as release build — how to debug?
...by a buffer overflow, caused a single byte difference:
char *end = static_cast<char*>(attr->data) + attr->dataSize;
This is a fencepost error (off-by-one error) and was fixed by:
char *end = static_cast<char*>(attr->data) + attr->dataSize - 1;
The weird thing was, I put...
Why unsigned integer is not available in PostgreSQL?
...pret strings as literals, just write '4294966272'::uint4 as your literals. Casts shouldn't be a huge deal either. You don't even need to do range exceptions, you can just treat the semantics of '4294966273'::uint4::int as -1024. Or you can throw an error.
If I wanted this, I would have done it. But...
Generic TryParse
...nverter(typeof(T));
if(converter != null)
{
// Cast ConvertFromString(string text) : object to (T)
return (T)converter.ConvertFromString(input);
}
return default(T);
}
catch (NotSupportedException)
{
return default(T);
}...
Why would finding a type's initializer throw a NullReferenceException?
...found at least 3 workaround approaches for fixing the problem:
Simply by casting the Type to _Type inside the Main method:
var cctor = ((_Type)typeof(Test)).TypeInitializer;
Or making sure that approach 1 was used previously inside the method:
var warmUp = ((_Type)typeof(Test)).TypeInitializer;...
Select distinct values from a table field
...t('city').distinct()
This one returns a ValuesListQuerySet which you can cast to a list.
You can also add flat=True to values_list to flatten the results.
See also: Get distinct values of Queryset by field
share
...
“’” showing on page instead of “ ' ”
...h several SQL queries like this...
UPDATE MyTable SET
MyField1 = CONVERT(CAST(CONVERT(MyField1 USING latin1) AS BINARY) USING utf8),
MyField2 = CONVERT(CAST(CONVERT(MyField2 USING latin1) AS BINARY) USING utf8);
Do this for as many tables/columns as necessary.
You can also fix some of these st...
How to see the CREATE VIEW code for a view in PostgreSQL?
...
@elias: just use the version that uses an OID by casting the name to an oid: select pg_get_viewdef('viewname'::regclass, true)
– a_horse_with_no_name
Jan 31 '13 at 20:44
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