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Convert.ChangeType() fails on Nullable Types
...ample, but this is a relatively robust approach, and separates the task of casting from unknown value to unknown type
I have a TryCast method that does something similar, and takes nullable types into account.
public static bool TryCast<T>(this object value, out T result)
{
var type = ty...
How to check if a table exists in a given schema
... dba.SE discussing "Information schema vs. system catalogs"
Alternative: cast to regclass
SELECT 'schema_name.table_name'::regclass
This raises an exception if the (optionally schema-qualified) table (or other object occupying that name) does not exist.
If you do not schema-qualify the table n...
SQL-Server: Error - Exclusive access could not be obtained because the database is in use
...@@spid
while (@spid is not null)
begin
print 'Killing process ' + cast(@spid as varchar) + ' ...'
set @sql = 'kill ' + cast(@spid as varchar)
exec (@sql)
select
@spid = min(spid)
from
master..sysprocesses
where
dbid = db_id('<database_n...
How do you determine what SQL Tables have an identity column programmatically
...alue
, CASE
WHEN last_value < 0 THEN 100
ELSE (1 - CAST(last_value AS FLOAT(4)) / max_value) * 100
END AS [percentLeft]
, CASE
WHEN CAST(last_value AS FLOAT(4)) / max_value >= @threshold
THEN 'warning: approaching max limit'
ELSE 'ok...
iPhone: How to get current milliseconds?
... the OS you might need to use 'long long' instead of a 'long' and likewise cast time.tv_sec to 'long long' before doing the rest of the calculation.
– AbePralle
Dec 1 '11 at 23:20
...
How to access random item in list?
...mString = strings.PickRandom();
If all you have is an ArrayList, you can cast it:
var strings = myArrayList.Cast<string>();
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Cocoa Touch: How To Change UIView's Border Color And Thickness?
...as You say. r, g and b can be int, as C (and objC IS C) promotions will cast int r=128 to double when making: r/255.0. By the way You got double, and Clang will cast to CGFloat.
– ingconti
Jan 28 '18 at 14:54
...
Convert HH:MM:SS string to seconds only in javascript
...nits multiplied by 60 as it goes through each unit.
The +time is used to cast the time to a number.
It basically ends up doing: (60 * ((60 * HHHH) + MM)) + SS
If only seconds is passed then the result would be a string, so to fix that we could cast the entire result to an int:
+('03'.split(':')...
How do I perform an IF…THEN in an SQL SELECT?
...osest to IF in SQL and is supported on all versions of SQL Server.
SELECT CAST(
CASE
WHEN Obsolete = 'N' or InStock = 'Y'
THEN 1
ELSE 0
END AS bit) as Saleable, *
FROM Product
You only need to do the CAST if you wa...
Why should I use a pointer rather than the object itself?
...back(&triangle);
for (auto& e : vector)
{
auto test = dynamic_cast<Triangle*>(e); // I only care about triangles
if (!test) // not a triangle
e.GenericFunction();
else
e.TriangleOnlyMagic();
}
So say if only Triangles had a Rotate function, it would be ...