大约有 2,600 项符合查询结果（耗时：0.0268秒） [XML]
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
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Why does int i = 1024 * 1024 * 1024 * 1024 compile without error?
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Right. Assigning an int to a long includes an implicit cast. But the value can never exist as the int in the first place to get casted :)
– Cruncher
Jul 11 '14 at 18:14
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How to get the groups of a user in Active Directory? (c#, asp.net)
...tity.GetCurrent().User;
var allDomains = Forest.GetCurrentForest().Domains.Cast<Domain>();
var allSearcher = allDomains.Select(domain =>
{
var searcher = new DirectorySearcher(new DirectoryEntry("LDAP://" + domain.Name));
// Apply some filter to focus on only some specfic objects
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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;...
How does virtual inheritance solve the “diamond” (multiple inheritance) ambiguity?
...nheritance diagrams to show the derived classes below the bases. (see "downcast", "upcast")
– peterh - Reinstate Monica
Jul 8 '16 at 20:27
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Find a string by searching all tables in SQL Server Management Studio 2008
...CT @Count = COUNT(1) FROM [dbo].[' + T.TABLE_NAME + '] WITH (NOLOCK) WHERE CAST([' + C.COLUMN_NAME +
'] AS NVARCHAR(MAX)) LIKE ''%' + @KeyWord + N'%''',
T.TABLE_NAME,
C.COLUMN_NAME
FROM INFORMATION_SCHEMA.TABLES AS T WITH (NOLOCK)
INNER JOIN INFORMATION...
Why doesn't Java offer operator overloading?
...and one double. There is even the whole pointer arithmetic domain (without casting, you can add to a pointer an integer, but you cannot add two pointers...).
In Java, there is no pointer arithmetic, but someone still found string concatenation without the + operator would be ridiculous enough to ju...
How do you create a dropdownlist from an enum in ASP.NET MVC?
...adata);
IEnumerable<TEnum> values = Enum.GetValues(enumType).Cast<TEnum>();
IEnumerable<SelectListItem> items = from value in values
select new SelectListItem
{
Text = GetEnumDescription(value),
Value = value....
vs in Generics
...of the generic class, interface or method. The implication is that you can cast the type/interface/method to an equivalent with a super-type of T.
E.g. ICovariant<out Dog> can be cast to ICovariant<Animal>.
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JavaScript plus sign in front of function expression
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Subsidiary to @TJCrowder's answer, + is usually used to force numerical casting of a value as this SO answer explains. In this instance it is called the 'unary plus operator' (for ease of googling).
var num = +variant;
So in front of a function it can be a way to force the function's result to...