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How to use if - else structure in a batch file?
...stion about if - else structure in a batch file. Each command runs individually, but I couldn't use "if - else" blocks safely so these parts of my programme doesn't work. How can I do make these parts run? Thank you.
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How to change the type of a field?
...(x)) and then save the document again.
If you need to do this programmatically and entirely from the shell, you can use the find(...).forEach(function(x) {}) syntax.
In response to the second comment below. Change the field bad from a number to a string in collection foo.
db.foo.find( { 'bad' :...
How to handle dependency injection in a WPF/MVVM application
...rd and it has a good documentation (and plenty of answers on SO).
So basically it goes like this:
Create the view model, and take the IStorage interface as constructor parameter:
class UserControlViewModel
{
public UserControlViewModel(IStorage storage)
{
}
}
Create a ViewModelLoca...
How to make an OpenGL rendering context with transparent background?
Rendering contexts usually have a solid color on the background (black or whatever, see the image below):
9 Answers
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Where is SQL Server Management Studio 2012?
... SQL Server 2008 R2 and Visual Studio 2008 and 2010 on my laptop. I've installed SQL Server 2012 and have finally got SQL Server Data Tools to show up, so that I can create SSRS reports in Visual Studio 2010.
...
print call stack in C or C++
Is there any way to dump the call stack in a running process in C or C++ every time a certain function is called? What I have in mind is something like this:
...
How do I find out which keystore was used to sign an app?
...ture algorithm name: SHA1withRSA
Then use the keytool again to print out all the aliases of your signing keystore:
keytool -list -keystore my-signing-key.keystore
You will get a list of aliases and their certificate fingerprint:
android_key, Jan 23, 2010, PrivateKeyEntry,
Certificate fingerpri...
How can I access and process nested objects, arrays or JSON?
...as any string can be used as key in objects. The key-value pairs are also called the "properties".
Properties can be accessed either using dot notation
const value = obj.someProperty;
or bracket notation, if the property name would not be a valid JavaScript identifier name [spec], or the name is...
What belongs in an educational tool to demonstrate the unwarranted assumptions people make in C/C++?
...ch should help beginners (and intermediate) programmers to recognize and challenge their unwarranted assumptions in C, C++ and their platforms.
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How to make my custom type to work with “range-based for loops”?
...hanges, and compilers that do not.
The objects returned do not have to actually be iterators. The for(:) loop, unlike most parts of the C++ standard, is specified to expand to something equivalent to:
for( range_declaration : range_expression )
becomes:
{
auto && __range = range_expressi...