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Swift: Testing optionals for nil
... // Do something using `xyz`.
}
This produces an error:
does not conform to protocol 'BooleanType.Protocol'
You have to use one of these forms:
if xyz != nil {
// Do something using `xyz`.
}
if let xy = xyz {
// Do something using `xy`.
}
...
Stop an input field in a form from being submitted
...ript (a greasemonkey/userscript) that will insert some input fields into a form on a website.
12 Answers
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form_for with nested resources
I have a two-part question about form_for and nested resources. Let's say I'm writing a blog engine and I want to relate a comment to an article. I've defined a nested resource as follows:
...
How to prevent form resubmission when page is refreshed (F5 / CTRL+R)
I have a simple form that submits text to my SQL table. The problem is that after the user submits the text, they can refresh the page and the data gets submitted again without filling the form again. I could redirect the user to another page after the text is submitted, but I want users to stay on ...
@RequestParam vs @PathVariable
... edited Apr 14 at 9:27
informatik01
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answered Nov 28 '19 at 11:59
...
Is “else if” a single keyword?
...he substatement in a selection-statement (each substatement, in the
else form of the if statement) implicitly defines a block scope (3.3).
If the substatement in a selection-statement is a single statement and
not a compound-statement, it is as if it was rewritten to be a
compound-statement ...
HTML5 Pre-resize images before uploading
...up with a solution which I believe executes quickly and has pretty good performance too - as the Mozilla solution of copying from 1 canvas to another works quickly and without loss of image quality at a 2:1 ratio, given a target of x pixels wide and y pixels tall, I use this canvas resizing method u...
What is a Manifest in Scala and when do you need it?
...
The compiler knows more information about types than the JVM runtime can easily represent. A Manifest is a way for the compiler to send an inter-dimensional message to the code at runtime about the type information that was lost.
This is similar to ...
Angular.js programmatically setting a form field to dirty
I am programmatically updating some of the fields on my form with a value and I would like to set the field state to $dirty . Doing something like:
...
Uploading images using Node.js, Express, and Mongoose
Please consider newer answers that have more up-to-date information as things have changed over the years!
12 Answers
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