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How do I check if an object has a specific property in JavaScript?
How do I check if an object has a specific property in JavaScript?
24 Answers
24
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How to test if a string is JSON or not?
... @Zalaboza 1234, 0, false, and null are all valid JSON values. If you want a predicate that tests if the JSON represents an object you'll need to do a little more.
– Michael Lang
Nov 18 '15 at 23:15
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Is it possible to determine whether ViewController is presented as Modal?
....presentingViewController isKindOfClass:[UITabBarController class]];
}
Swift:
var isModal: Bool {
return self.presentingViewController?.presentedViewController == self
|| (self.navigationController != nil && self.navigationController?.presentingViewController?.presentedViewCon...
javascript set a variable if undefined
I know that I can test for a javascript variable and then define it if it is undefined, but is there not some way of saying
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MDI CDockablePane使用总结 - C/C++ - 清泛网 - 专注C/C++及内核技术
...：
CMFCPopupMenu::SetForceMenuFocus(FALSE);
InitUserToolbars(NULL, uiFirstUserToolBarId, uiLastUserToolBarId);
EnablePaneMenu(TRUE, ID_VIEW_CUSTOMIZE, 0, ID_VIEW_TOOLBAR);
CDockingManager::SetDockingMode(DT_SMART);
EnableAutoHidePanes(CBRS_ALIGN_ANY);
EnableDocking(CBRS_ALIGN_ANY);
（...
Testing if jQueryUI has loaded
...te, and I think that jQueryUI may not have loaded properly. How can I test if jQueryUI has loaded?
5 Answers
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std::enable_if to conditionally compile a member function
...ying to get a simple example to work to understand how to use std::enable_if . After I read this answer , I thought it shouldn't be too hard to come up with a simple example. I want to use std::enable_if to choose between two member-functions and allow only one of them to be used.
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Efficient way to remove keys with empty strings from a dict
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Python 2.X
dict((k, v) for k, v in metadata.iteritems() if v)
Python 2.7 - 3.X
{k: v for k, v in metadata.items() if v is not None}
Note that all of your keys have values. It's just that some of those values are the empty string. There's no such thing as a key in a dict w...
How can one check to see if a remote file exists using PHP?
The best I could find, an if fclose fopen type thing, makes the page load really slowly.
22 Answers
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How do I check if a C++ std::string starts with a certain string, and convert a substring to an int?
...verload of rfind which has the pos parameter:
std::string s = "tititoto";
if (s.rfind("titi", 0) == 0) {
// s starts with prefix
}
Who needs anything else? Pure STL!
Many have misread this to mean "search backwards through the whole string looking for the prefix". That would give the wrong res...