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Removing item from vector, while in C++11 range 'for' loop?
...
No, you can't. Range-based for is for when you need to access each element of a container once.
You should use the normal for loop or one of its cousins if you need to modify the container as you go along, access an element more than once, or ot...
Django Admin - Disable the 'Add' action for a specific model
...rgs):
form = super().get_form(request, obj, **kwargs)
form.base_fields['service'].widget.can_add_related = False
return form
In my case I use inline
# In inline formset e.g. admin.TabularInline
# disable all
def get_formset(self, request, obj=None, **kwargs):
f...
How do you configure Django for simple development and deployment?
...ings files.
settings_local.py - host-specific configuration, such as database name, file paths, etc.
settings_development.py - configuration used for development, e.g. DEBUG = True.
settings_production.py - configuration used for production, e.g. SERVER_EMAIL.
I tie these all together with a set...
How can I use optional parameters in a T-SQL stored procedure?
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Dynamically changing searches based on the given parameters is a complicated subject and doing it one way over another, even with only a very slight difference, can have massive performance implications. The key is to use an index, ignore compact code, i...
What are some good Python ORM solutions? [closed]
...()
foo_id = Int()
foo = Reference(foo_id, Foo.id)
db = create_database('sqlite:')
store = Store(db)
foo = Foo()
store.add(foo)
thing = Thing()
thing.foo = foo
store.add(thing)
store.commit()
And it makes it painless to drop down into raw SQL when you need to:
store.execute('UPDATE bars ...
How to set the margin or padding as percentage of height of parent container?
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top works great for resizing based on browser/window height. How aboutt having a div underneath that div? How can you clear the 2nd div to be under the div that is shifted down by a top:50%??
– Federico
Nov 19 '14 a...
How do I make a request using HTTP basic authentication with PHP curl?
...
CURLOPT_USERPWD basically sends the base64 of the user:password string with http header like below:
Authorization: Basic dXNlcjpwYXNzd29yZA==
So apart from the CURLOPT_USERPWD you can also use the HTTP-Request header option as well like below with other head...
Convert Data URI to File then append to FormData
...ert a dataURI to a Blob:
function dataURItoBlob(dataURI) {
// convert base64/URLEncoded data component to raw binary data held in a string
var byteString;
if (dataURI.split(',')[0].indexOf('base64') >= 0)
byteString = atob(dataURI.split(',')[1]);
else
byteString =...
Preview an image before it is uploaded
...lt);
}
reader.readAsDataURL(input.files[0]); // convert to base64 string
}
}
$("#imgInp").change(function() {
readURL(this);
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<form runat="server">
<input ...
What does this square bracket and parenthesis bracket notation mean [first1,last1)?
... offset depending on which field are you in:
Mathematics tends to be one-based.
Certain programming languages tends to be zero-based, such as C, C++, Javascript, Python, while other languages such as Mathematica, Fortran, Pascal are one-based.
These differences can lead to subtle fence post er...