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How do I convert an enum to a list in C#? [duplicate]
...meEnum> of all the values of an Enum.
Enum.GetValues(typeof(SomeEnum)).Cast<SomeEnum>();
If you want that to be a List<SomeEnum>, just add .ToList() after .Cast<SomeEnum>().
To use the Cast function on an Array you need to have the System.Linq in your using section.
...
Unable to cast object of type 'System.DBNull' to type 'System.String`
... There are several scenarios where you might prefer convert to an explicit cast. @romanm noted one of them. Another one is when you work with decimals and care about the different rounding mechanisms that Convert.ToInt32 and (int) use. The former rounds to the nearest even value, while the explicit ...
Return Boolean Value on SQL Select Statement
...N EXISTS (
SELECT *
FROM [User]
WHERE UserID = 20070022
)
THEN CAST(1 AS BIT)
ELSE CAST(0 AS BIT) END
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What is a void pointer in C++? [duplicate]
... it stores which kinds of objects, and therefore which type you can safely cast it to.
This construct is nothing like dynamic or object in C#. Those tools actually know what the original type is; void* does not. This makes it far more dangerous than any of those, because it is very easy to get it ...
Direct casting vs 'as' operator?
...
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...
Converting stream of int's to char's in java
...et, or use InputStreamReader with the appropriate Charset instead.
Simply casting from int to char only works if you want ISO-8859-1, if you're reading bytes from a stream directly.
EDIT: If you are already using a Reader, then casting the return value of read() to char is the right way to go (aft...
error: cannot dynamic_cast ‘b’ (of type ‘class Base*’) to type ‘c...
error: cannot dynamic_cast ‘b’ (of type ‘class Base*’) to type ‘class Derived*’ (source type is not polymorphic)在将父类型转换为子类型时,可以使用static_cast和dynamic_cast.如果使用dynamic_cast,它要求父类必须为多态的,即要求至少有一个虚函数,因此....
What's Mongoose error Cast to ObjectId failed for value XXX at path “_id”?
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Mongoose's findById method casts the id parameter to the type of the model's _id field so that it can properly query for the matching doc. This is an ObjectId but "foo" is not a valid ObjectId so the cast fails.
This doesn't happen with 41224d776a326...
How to convert a double to long without casting?
What is the best way to convert a double to a long without casting?
9 Answers
9
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How to compare dates in datetime fields in Postgresql?
...
@Nicolai is correct about casting and why the condition is false for any data. i guess you prefer the first form because you want to avoid date manipulation on the input string, correct? you don't need to be afraid:
SELECT *
FROM table
WHERE update...