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How to “test” NoneType in python?
...statement:
if isinstance(x, type(None)):
#do stuff
Additional information
You can also check for multiple types in one isinstance() statement as mentioned in the documentation. Just write the types as a tuple.
isinstance(x, (type(None), bytes))
...
What is Normalisation (or Normalization)?
...ata corruption.
There is a number of normalization levels from 1. normal form through 5. normal form. Each normal form describes how to get rid of some specific problem, usually related to redundancy.
Some typical normalization errors:
(1) Having more than one value in a cell. Example:
UserId |...
Getting full URL of action in ASP.NET MVC [duplicate]
...script which is beneficial in many situations.
UPDATE: The way to get url formed outside of the page itself is well described in answers above.
Or you could do a oneliner like following:
new UrlHelper(actionExecutingContext.RequestContext).Action(
"SessionTimeout", "Home",
new {area = s...
Why java.util.Optional is not Serializable, how to serialize the object with such fields
...ion related problems can be solved by decoupling the persistent serialized form from the actual runtime implementation you operate on.
/** The class you work with in your runtime */
public class My implements Serializable {
private static final long serialVersionUID = 1L;
Optional<Integ...
How do you handle multiple submit buttons in ASP.NET MVC Framework?
Is there some easy way to handle multiple submit buttons from the same form? For example:
35 Answers
...
How do I drag and drop files into an application?
...
Some sample code:
public partial class Form1 : Form {
public Form1() {
InitializeComponent();
this.AllowDrop = true;
this.DragEnter += new DragEventHandler(Form1_DragEnter);
this.DragDrop += new DragEventHandler(Form1_DragDrop);
}
...
Django: Redirect to previous page after login
... page. When clicking on the login link the user will be taken to the login form. After a successful login the user should be taken back to the page from where he clicked the login link in the first place.
I'm guessing that I have to somehow pass the url of the current page to the view that handles t...
How to set the Default Page in ASP.NET?
...ll it could be. I think the simple thing would be like Application.Run(new Form()1) :)
– Tarik
Dec 16 '09 at 8:20
@Arr...
How to round a number to n decimal places in Java
...ode explicitly to handle your issue with the half-even round, then use the format pattern for your required output.
Example:
DecimalFormat df = new DecimalFormat("#.####");
df.setRoundingMode(RoundingMode.CEILING);
for (Number n : Arrays.asList(12, 123.12345, 0.23, 0.1, 2341234.212431324)) {
D...
Mimicking sets in JavaScript?
... keys in the Set
// returns the original key (not the string converted form)
keys: function() {
var results = [];
this.each(function(data) {
results.push(data);
});
return results;
},
// clears the Set
clear: function() {
this.d...