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Throwing exceptions from constructors
...
Not really, in this specific case, note that his Mutex destructor will never be called, possibly leaking the pthread mutex. The solution to that is to use a smart pointer for the pthread mutex, better yet use boost mutexes or std::mutex, no reason t...
How to RedirectToAction in ASP.NET MVC without losing request data
...can go:
public ActionResult Form()
{
/* Declare viewData etc. */
if (TempData["form"] != null)
{
/* Cast TempData["form"] to
System.Collections.Specialized.NameValueCollection
and use it */
}
return View("Form", viewData);
}
...
Android; Check if file exists without creating a new one
I want to check if file exists in my package folder, but I don't want to create a new one.
7 Answers
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Python json.loads shows ValueError: Extra data
...)
ValueError: Extra data: line 1 column 3 - line 1 column 5 (char 2 - 4)
If you want to dump multiple dictionaries, wrap them in a list, dump the list (instead of dumping dictionaries multiple times)
>>> dict1 = {}
>>> dict2 = {}
>>> json.dumps([dict1, dict2])
'[{}, {}]...
Why is it faster to check if dictionary contains the key, rather than catch the exception in case it
...eration.
BTW: The correct way to do this is to use TryGetValue
obj item;
if(!dict.TryGetValue(name, out item))
return null;
return item;
This accesses the dictionary only once instead of twice.
If you really want to just return null if the key doesn't exist, the above code can be simplified ...
Get exit code of a background process
...put and decide how close it is to finishing. (ps | grep isn't idiot-proof. If you have time you can come up with a more robust way to tell whether the process is still running).
Here's a skeleton script:
# simulate a long process that will have an identifiable exit code
(sleep 15 ; /bin/false) &...
Python Dictionary to URL Parameters
...nverts it into a form suitable for a URL (e.g., key1=val1&key2=val2).
If you are using Python3, use urllib.parse.urlencode()
If you want to make a URL with repetitive params such as: p=1&p=2&p=3 you have two options:
>>> import urllib
>>> a = (('p',1),('p',2), ('p', ...
How to break out of jQuery each Loop
...to a continue in a normal loop.
$.each(array, function(key, value) {
if(value === "foo") {
return false; // breaks
}
});
// or
$(selector).each(function() {
if (condition) {
return false;
}
});
s...
Show hide fragment in android
...R.animator.fade_out)
.show(somefrag)
.commit();
OR if you are using android.support.v4.app.Fragment
FragmentManager fm = getSupportFragmentManager();
fm.beginTransaction()
.setCustomAnimations(android.R.anim.fade_in, android.R.anim.fade_out)
.show(somef...
Detect if Visual C++ Redistributable for Visual Studio 2012 is installed
How to detect if Visual C++ Redistributable for Visual Studio 2012 is installed?
20 Answers
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