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Downcasting shared_ptr to shared_ptr?
...le is like the one in Boost, but it doesn't support shared_polymorphic_downcast (or dynamic_pointer_cast or static_pointer_cast for that matter)!
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Cast List to List
How can I cast List<Client> to List<IDic> ?
8 Answers
8
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Direct casting vs 'as' operator?
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string s = (string)o; // 1
Throws InvalidCastException if o is not a string. Otherwise, assigns o to s, even if o is null.
string s = o as string; // 2
Assigns null to s if o is not a string or if o is null. For this reason, you cannot use it with value types (th...
Imply bit with constant 1 or 0 in SQL Server
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cast (
case
when FC.CourseId is not null then 1 else 0
end
as bit)
The CAST spec is "CAST (expression AS type)". The CASE is an expression in this context.
If you have multiple such expressions, I'd declare bit var...
Finding the type of an object in C++
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dynamic_cast should do the trick
TYPE& dynamic_cast<TYPE&> (object);
TYPE* dynamic_cast<TYPE*> (object);
The dynamic_cast keyword casts a datum from one pointer or reference type to another, performing a runtime ...
Base64 encoding in SQL Server 2005 T-SQL
...-- Encode the string "TestData" in Base64 to get "VGVzdERhdGE="
SELECT
CAST(N'' AS XML).value(
'xs:base64Binary(xs:hexBinary(sql:column("bin")))'
, 'VARCHAR(MAX)'
) Base64Encoding
FROM (
SELECT CAST('TestData' AS VARBINARY(MAX)) AS bin
) AS bin_sql_server_temp;
-- De...
What is the difference between up-casting and down-casting with respect to class variable
What is the difference between up-casting and down-casting with respect to class variable?
10 Answers
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Best approach to remove time part of datetime in SQL Server
...w etc by changing "0" base
Edit, Oct 2011
For SQL Server 2008+, you can CAST to date i.e. CAST(getdate() AS date). Or just use date datatype so no time to remove.
Edit, Jan 2012
A worked example of how flexible this is: Need to calculate by rounded time or date figure in sql server
Edit, May 2...
Get the week start date and week end date from week number
...f-week value. Here is an example:
WITH TestData(SomeDate) AS (
SELECT CAST('20001225' AS DATETIME) UNION ALL
SELECT CAST('20001226' AS DATETIME) UNION ALL
SELECT CAST('20001227' AS DATETIME) UNION ALL
SELECT CAST('20001228' AS DATETIME) UNION ALL
SELECT CAST('20001229' AS DATETI...
How do I cast a string to integer and have 0 in case of error in the cast with PostgreSQL?
...conditionals, so you shouldn't get any non-integers hitting your ::integer cast. It also handles NULL values (they won't match the regexp).
If you want zeros instead of not selecting, then a CASE statement should work:
SELECT CASE WHEN myfield~E'^\\d+$' THEN myfield::integer ELSE 0 END FROM mytabl...