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C++ equivalent of StringBuffer/StringBuilder?
...eam or just plain string concatenations. C++ strings are mutable so the performance considerations of concatenation are less of a concern.
with regards to formatting, you can do all the same formatting on a stream, but in a different way, similar to cout. or you can use a strongly typed functor whi...
Open file dialog box in JavaScript
...is will cause IE to throw an error if you end up submitting the associated form programmatically as well.
– Ray Nicholus
Oct 22 '13 at 21:48
...
Begin, Rescue and Ensure in Ruby?
...rror, ScriptError, Interrupt, SignalException or SystemExit.)
Some blocks form implicit exception blocks. For example, method definitions are implicitly also exception blocks, so instead of writing
def foo
begin
# ...
rescue
# ...
end
end
you write just
def foo
# ...
rescue
# ...
Can I make the foreign key field optional in Django model
...ent because typically if you're going to allow a field to be blank in your form, you're going to also need your database to allow NULL values for that field. The exception is CharFields and TextFields, which in Django are never saved as NULL. Blank values are stored in the DB as an empty string (''...
iPad keyboard will not dismiss if modal ViewController presentation style is UIModalPresentationForm
...r reasoning is that the user is often going to be entering data in a modal form so they are trying to be "helpful" and keep the keyboard visible where ordinarily various transitions within the modal view can cause the keyboard to show/hide repeatedly.
edit: here is the response of an Apple engineer...
Convert Data URI to File then append to FormData
...k is to extract an image file from the canvas object and append it to a FormData object for upload.
14 Answers
...
Run command on the Ansible host
... work with command? Because as far as I know we cannot use the param free_form to define the command that will be executed
– Ander
Sep 8 '16 at 4:40
...
Preview an image before it is uploaded
...ogleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<form runat="server">
<input type='file' id="imgInp" />
<img id="blah" src="#" alt="your image" />
</form>
Also, you can try this sample here.
...
Cloning a private Github repo
...
Private clone URLs take the form git@github.com:username/repo.git - perhaps you needed to use git@ rather than git://?
git:// URLs are read only, and it looks like private repos do not allow this form of access.
...
What's the syntax for mod in java
...l add a bit of additional context. % the "modulus" operator is actually performing the remainder operation. The difference between mod and rem is subtle, but important.
(-1 mod 2) would normally give 1. More specifically given two integers, X and Y, the operation (X mod Y) tends to return a value...