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Nullable type as a generic parameter possible?
...>, and call the method with the non nullable parameter
static void Main(string[] args)
{
int? i = GetValueOrNull<int>(null, string.Empty);
}
public static Nullable<T> GetValueOrNull<T>(DbDataRecord reader, string columnName) where T : struct
{
object columnValue = read...
Calculating days between two dates with Java
...asses.
DateTimeFormatter dtf = DateTimeFormatter.ofPattern("dd MM yyyy");
String inputString1 = "23 01 1997";
String inputString2 = "27 04 1997";
try {
LocalDateTime date1 = LocalDate.parse(inputString1, dtf);
LocalDateTime date2 = LocalDate.parse(inputString2, dtf);
long daysBetween =...
Java List.add() UnsupportedOperationException
I try to add objects to a List<String> instance but it throws an UnsupportedOperationException .
Does anyone know why?
...
Is there a string math evaluator in .NET?
If I have a string with a valid math expression such as:
16 Answers
16
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Php multiple delimiters in explode
I have a problem, I have a string array, and I want to explode in different delimiter. For Example
12 Answers
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How to extract the first two characters of a string in shell scripting?
...sh shell (and you appear to be, based on your comments), is to use the sub-string variant of parameter expansion:
pax> long="USCAGol.blah.blah.blah"
pax> short="${long:0:2}" ; echo "${short}"
US
This will set short to be the first two characters of long. If long is shorter than two characte...
How to find NSDocumentDirectory in Swift?
...
This answer failed in Xcode 6.0. The cast must be to NSString rather than String.
– Daniel T.
Oct 19 '14 at 16:15
1
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Fast permutation -> number -> permutation mapping algorithms
...algorithm is awesome, but I just found several cases to be wrong. Take the string "123"; the 4th permutation should be 231, but according to this algorithm, it will be 312. say 1234, the 4th permutation should be 1342, but it will be mistaken to be "1423". Correct me if I observed wrong. Thanks.
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How can I perform a str_replace in JavaScript, replacing text in JavaScript?
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Using regex for string replacement is significantly slower than using a string replace.
As demonstrated on JSPerf, you can have different levels of efficiency for creating a regex, but all of them are significantly slower than a simple strin...
What is LDAP used for?
...ibutes has a type and one or more values. The types are typically mnemonic strings, like cn for common name, or mail for email address. The syntax of values depend on the attribute type. For example, a cn attribute might contain the value Babs Jensen. A mail attribute might contain the value babs@ex...