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java: HashMap not working
...s aren't retained at runtime. They are just "syntactic sugar" for explicit casting to save you doing this:
Integer i = (Integer)myMap.get("foo");
To give you an example, this code is perfectly legal:
Map<String, Integer> myMap = new HashMap<String, Integer>();
Map<Integer, String&...
How to pass a single object[] to a params object[]
...
A simple typecast will ensure the compiler knows what you mean in this case.
Foo((object)new object[]{ (object)"1", (object)"2" }));
As an array is a subtype of object, this all works out. Bit of an odd solution though, I'll agree.
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SQLite DateTime comparison
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Sqlite can not compare on dates. we need to convert into seconds and cast it as integer.
Example
SELECT * FROM Table
WHERE
CAST(strftime('%s', date_field) AS integer) <=CAST(strftime('%s', '2015-01-01') AS integer) ;
...
convert a list of objects from one type to another using lambda expression
...ound when (or if) it can be used. I just tried it and was getting a cannot cast expression exception
– Collin M. Barrett
Aug 1 '18 at 16:26
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Using isKindOfClass with Swift
...nted out in @Kevin's answer, the correct way would be to use optional type cast operator as?. You can read more about it on the section Optional Chaining sub section Downcasting.
Edit 2
As pointed on the other answer by user @KPM, using the is operator is the right way to do it.
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Timer function to provide time in nano seconds using C++
..."rdtsc" : "=a" (lo), "=d" (hi));
return time_point(duration(static_cast<rep>(hi) << 32 | lo));
}
};
} // x
All this clock does is count CPU cycles and store it in an unsigned 64-bit integer. You may need to tweak the assembly language syntax for your compiler. Or your c...
C++ catch blocks - catch exception by value or reference? [duplicate]
...onst object and catch it with a non-const reference. To avoid this silent "casting away" of const, always catch a const reference, and ensure your exception types have const-correct accessors.
– Daniel Earwicker
Mar 26 '10 at 10:01
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error C2440: \'initializing\' : cannot convert from \'char *\' to \'co...
...har> > *'
Types pointed to are unrelated; conversion requires reinterpret_cast, C-style cast or function-style cast
//输出一行中所有字符
void printchar(string &line)
{
istringstream iss(line);
string word;
while(iss>>word)
for(vector<string>::const_...
Sql Server string to date conversion
...
Try this
Cast('7/7/2011' as datetime)
and
Convert(varchar(30),'7/7/2011',102)
See CAST and CONVERT (Transact-SQL) for more details.
share
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How to set enum to null
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@equiman no need to cast since the type is specified on the left, you are basically duplicating the first part of my answer that is already accepted.
– Rodney S. Foley
Jul 8 '15 at 22:50
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