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Determine if a String is an Integer in Java [duplicate]
I'm trying to determine if a particular item in an Array of strings is an integer or not.
9 Answers
...
Add column to SQL Server
... use the ALTER TABLE... syntax.
Example
ALTER TABLE YourTable
ADD Foo INT NULL /*Adds a new int column existing rows will be
given a NULL value for the new column*/
Or
ALTER TABLE YourTable
ADD Bar INT NOT NULL DEFAULT(0) /*Adds a new int column existing rows will
...
Why is the gets function so dangerous that it should not be used?
... you want to use fgets, which has the signature
char* fgets(char *string, int length, FILE * stream);
(fgets, if it reads an entire line, will leave the '\n' in the string; you'll have to deal with that.)
It remained an official part of the language up to the 1999 ISO C standard, but
it was offi...
Bidirectional 1 to 1 Dictionary in C#
...mber of pairs stored in the dictionary
/// </summary>
public Int32 Count
{
get { return firstToSecond.Count; }
}
/// <summary>
/// Removes all items from the dictionary.
/// </summary>
public void Clear()
{
firstToSecond.Clear();...
How to change current Theme at runtime in Android [duplicate]
...like this:
TaskStackBuilder.create(getActivity())
.addNextIntent(new Intent(getActivity(), MainActivity.class))
.addNextIntent(getActivity().getIntent())
.startActivities();
EDIT:
Just put the code above after you perform changing of theme on the UI or som...
Remove Primary Key in MySQL
...
Without an index, maintaining an autoincrement column becomes too expensive, that's why MySQL requires an autoincrement column to be a leftmost part of an index.
You should remove the autoincrement property before dropping the key:
ALTER TABLE...
Iterating C++ vector from the end to the beginning
...ere especially designed for that purpose. (And yes, incrementing a reverse_interator moves it backward.)
Now, in theory, your method (using begin()/end() & --i) would work, std::vector's iterator being bidirectional, but remember, end() isn't the last element — it's one beyond the last elemen...
Do you have to put Task.Run in a method to make it async?
...o the calling thread before it starts. In an async method, those "yield" points are await expressions.
This is very different than the term "asynchronous", as (mis)used by the MSDN documentation for years to mean "executes on a background thread".
To futher confuse the issue, async is very differe...
What exactly is a reentrant function?
...
{
foo(nullptr);
}
At first sight, everything seems ok… But wait:
int main()
{
foo(bar);
return 0;
}
If the lock on mutex is not recursive, then here's what will happen, in the main thread:
main will call foo.
foo will acquire the lock.
foo will call bar, which will call foo.
th...
How do you trigger a block after a delay, like -performSelector:withObject:afterDelay:?
... using performSelector:withObject:afterDelay: but with an argument like int / double / float ?
19 Answers
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