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Coalesce function for PHP?
...HP 7 introduced a real coalesce operator:
echo $_GET['doesNotExist'] ?? 'fallback'; // prints 'fallback'
If the value before the ?? does not exists or is null the value after the ?? is taken.
The improvement over the mentioned ?: operator is, that the ?? also handles undefined variables without...
The relationship could not be changed because one or more of the foreign-key properties is non-nulla
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You should delete old child items thisParent.ChildItems one by one manually. Entity Framework doesn't do that for you. It finally cannot decide what you want to do with the old child items - if you want to throw them away or if you want to keep and assign them to other parent entities. You must ...
Best way to check if a URL is valid
...mal text. The function or solution, that I'm looking for, should recognize all links formats including the ones with GET parameters.
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How can I programmatically check whether a keyboard is present in iOS app?
... responder. I have a view controller with multiple child view controllers, all of which contain UITextFields. Using this method, i cannot tell from my parent view controller whether the keyboard is shown. The only reliable way is to use the notification method explained in the other answers
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php中json_decode()和json_encode()的使用方法 - 更多技术 - 清泛网 - 专注C/C++及内核技术
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echo "Unicode: ", json_encode($a, JSON_UNESCAPED_UNICODE), "\n";
echo "All: ", json_encode($a, JSON_HEX_TAG | JSON_HEX_APOS | JSON_HEX_QUOT | JSON_HEX_AMP | JSON_UNESCAPED_UNICODE), "\n\n";
$b = array();
echo "Empty array output as array: ", json_encode($b), "\n";
echo "Empty array out...
Convert objective-c typedef to its string equivalent
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This is really a C question, not specific to Objective-C (which is a superset of the C language). Enums in C are represented as integers. So you need to write a function that returns a string given an enum value. There are many ways to...
Creating an API for mobile applications - Authentication and Authorization
... criteria my be misguided so feel free to critique that as well). Additionally, I want the API to be the same for all platforms/applications consuming it.
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LINQ to Entities case sensitive comparison
...ObjectQuery.ToTraceString to see the generated SQL query that has been actually submitted to SQL Server reveals the mystery:
string sqlQuery = ((ObjectQuery)context.Thingies
.Where(t => t.Name == "ThingamaBob")).ToTraceString();
When you create a LINQ to Entities query, LINQ to Entities ...
No output to console from a WPF application?
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You'll have to create a Console window manually before you actually call any Console.Write methods. That will init the Console to work properly without changing the project type (which for WPF application won't work).
Here's a complete source code example, of how a C...
Getting All Variables In Scope
Is there a way to get all variables that are currently in scope in javascript?
10 Answers
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