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Two-way encryption: I need to store passwords that can be retrieved
I am creating an application that will store passwords, which the user can retrieve and see. The passwords are for a hardware device, so checking against hashes are out of the question.
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Should I use Java date and time classes or go with a 3rd party library like Joda Time?
...ting a web based system which will be used in countries from all over the world. One type of data which must be stored is dates and times.
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Check that an email address is valid on iOS [duplicate]
...String : laxString;
NSPredicate *emailTest = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", emailRegex];
return [emailTest evaluateWithObject:checkString];
}
Discussion on Lax vs. Strict - http://blog.logichigh.com/2010/09/02/validating-an-e-mail-address/
And because categories are ju...
How can I programmatically determine if my app is running in the iphone simulator?
As the question states, I would mainly like to know whether or not my code is running in the simulator, but would also be interested in knowing the specific iphone version that is running or being simulated.
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What is difference between XML Schema and DTD?
... XML schema and DTD (document type definition), and why the XML schema is more powerful compared to DTD.
12 Answers
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How do I log errors and warnings into a file?
How do I turn on all error and warnings and log them to a file, but to set up all of that within the script (not changing anything in php.ini)?
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What is the difference between Amazon S3 and Amazon EC2 instance?
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An EC2 instance is like a remote computer running Windows or Linux and on which you can install whatever software you want, including a Web server running PHP code and a database server.
Amazon S3 is just a storage service, typically used to store large binary files. Amazon also ha...
Difference between binary tree and binary search tree
...ch node has up to two leaves
1
/ \
2 3
Binary search tree: Used for searching. A binary tree where the left child contains only nodes with values less than the parent node, and where the right child only contains nodes with values greater than or equal to the parent.
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/ \
1 3
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Adding div element to body or document in JavaScript
I am creating a light box in pure JavaScript. For that I am making an overlay. I want to add this overlay to body but I also want to keep the content on the page. My current code adds the overlay div but it also removes the current contents in body. How to add div element and keep contents on body?...
What is the preferred syntax for defining enums in JavaScript?
What is the preferred syntax for defining enums in JavaScript? Something like:
48 Answers
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