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django: BooleanField, how to set the default value to true?
...fields/#django.forms.Field.initial ) like
class MyForm(forms.Form):
my_field = forms.BooleanField(initial=True)
If you're using a ModelForm, you can set a default value on the model field ( https://docs.djangoproject.com/en/2.2/ref/models/fields/#default ), which will apply to the resulting M...
How to change the foreign key referential action? (behavior)
... means that if you delete a row from the parent table (Users in this case) all referencing rows from the child table (UserDetails) are also deleted.
– edruid
Jan 11 '18 at 14:20
1
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The order of elements in Dictionary
...when enumerating them:
foreach (KeyValuePair<string, string> kvp in _Dictionary.OrderBy(k => k.Value)) {
...
}
In framework 2.0 you would first have to put the items in a list in order to sort them:
List<KeyValuePair<string, string>> items = new List<KeyValuePair<str...
Printing all global variables/local variables?
How can I print all global variables/local variables? Is that possible in gdb?
3 Answers
...
Send email with PHPMailer - embed image in body
...PHPMailer, with images.
The body is loaded from a html file, that contains all the info.
2 Answers
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How can I read a whole file into a string variable
I have lots of small files, I don't want to read them line by line.
5 Answers
5
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How to remove last n characters from every element in the R vector
... an example of what I would do. I hope it's what you're looking for.
char_array = c("foo_bar","bar_foo","apple","beer")
a = data.frame("data"=char_array,"data2"=1:4)
a$data = substr(a$data,1,nchar(a$data)-3)
a should now contain:
data data2
1 foo_ 1
2 bar_ 2
3 ap 3
4 b 4
...
Populating a ListView using an ArrayList?
... @ Amokrane Chentir: I think that the "setContentView" method must be called before "findViewById" or else no ListView will be found.
– Petru
Jun 26 '12 at 20:36
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Why can lambdas be better optimized by the compiler than plain functions?
...assing them to a function template will instantiate a new function specifically for that object. The compiler can thus trivially inline the lambda call.
For functions, on the other hand, the old caveat applies: a function pointer gets passed to the function template, and compilers traditionally hav...
ASP.NET MVC 3 Razor: Include JavaScript file in the head tag
...JavaScript file for a particular *.cshtml to be in the head tag along with all the other include files that are defined in _Layout.cshtml.
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