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Unique fields that allow nulls in Django

...here is that the normalized "blank" value for a form CharField is an empty string, not None. So if you leave the field blank, you get an empty string, not NULL, stored in the DB. Empty strings are equal to empty strings for uniqueness checks, under both Django and database rules. You can force the...
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How can I clear or empty a StringBuilder? [duplicate]

I'm using a StringBuilder in a loop and every x iterations I want to empty it and start with an empty StringBuilder , but I can't see any method similar to the .NET StringBuilder.Clear in the documentation, just the delete method which seems overly complicated. ...
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C++ Structure Initialization

...er. And dot notation is way safer if you happen to add the same type (like char*) as one of the other members above or below in the structure, because there's no risk of swapping them. – Gui13 Nov 16 '16 at 9:21 ...
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Determine a string's encoding in C#

Is there any way to determine a string's encoding in C#? 9 Answers 9 ...
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Measuring execution time of a function in C++

...usage: #include <iostream> #include <algorithm> typedef std::string String; //first test function doing something int countCharInString(String s, char delim){ int count=0; String::size_type pos = s.find_first_of(delim); while ((pos = s.find_first_of(delim, pos)) != String:...
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Difference between class and type

...pe . For example, should the object "Hello World!" belong to the type String or class String ? Or maybe both? 5 An...
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convert a list of objects from one type to another using lambda expression

.... List<char> c = new List<char>() { 'A', 'B', 'C' }; List<string> s = c.Select(x => x.ToString()).ToList(); share | improve this answer | follow ...
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How does this milw0rm heap spraying exploit work?

...code. unscape will be used to put the sequence of bytes represented of the string in the spray variable. It's valid x86 code that fills a large chunk of the heap and jumps to the start of shellcode. The reason for the ending condition is string length limitations of the scripting engine. You can't h...
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How to display multiple notifications in android

...intent will direct to different activity.. private void sendNotification(String message,String title,JSONObject extras) throws JSONException { String id = extras.getString("actionParam"); Log.e("gcm","id = "+id); Intent intent = new Intent(this, OrderDetailActivty.class); intent.pu...
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PendingIntent does not send Intent extras

... Following code should work:- int icon = R.drawable.icon; String message = "hello"; long when = System.currentTimeMillis(); NotificationManager notificationManager = (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE); Notification notification = new Notific...