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How do I make a textbox that only accepts numbers?
... with this two event handlers on a standard TextBox:
private void textBox1_KeyPress(object sender, KeyPressEventArgs e)
{
if (!char.IsControl(e.KeyChar) && !char.IsDigit(e.KeyChar) &&
(e.KeyChar != '.'))
{
e.Handled = true;
}
// only allow one de...
Format floats with standard json module
...ckage). E.g., this code:
import json
from json import encoder
encoder.FLOAT_REPR = lambda o: format(o, '.2f')
print(json.dumps(23.67))
print(json.dumps([23.67, 23.97, 23.87]))
emits:
23.67
[23.67, 23.97, 23.87]
as you desire. Obviously, there should be an architected way to override FLOAT_REP...
Characters allowed in a URL
...738 specification:
Thus, only alphanumerics, the special characters "$-_.+!*'(),", and
reserved characters used for their reserved purposes may be used
unencoded within a URL.
EDIT: As @Jukka K. Korpela correctly points out, this RFC was updated by RFC 3986.
This has expanded and clarified...
Encoding an image file with base64
...long the lines of:
import base64
with open("yourfile.ext", "rb") as image_file:
encoded_string = base64.b64encode(image_file.read())
You have to open the file first of course, and read its contents - you cannot simply pass the path to the encode function.
Edit:
Ok, here is an update after y...
How to avoid “if” chains?
...the basic flow, e.g. instead of
if (ok)
{
DoSomething();
}
else
{
_log.Error("oops");
return;
}
... you'd use....
if (!ok)
{
_log.Error("oops");
return;
}
DoSomething(); //notice how this is already farther to the left than the example above
When there is a long series of ...
Is it possible to await an event instead of another async method?
...kCompletionSource<object> continueClicked;
private async void Button_Click_1(object sender, RoutedEventArgs e)
{
// Note: You probably want to disable this button while "in progress" so the
// user can't click it twice.
await GetResults();
// And re-enable the button here, possibly ...
Open URL in same window and in same tab
...eed to use the name attribute:
window.open("https://www.youraddress.com","_self")
Edit: Url should be prepended with protocol. Without it tries to open relative url. Tested in Chrome 59, Firefox 54 and IE 11.
share
...
Python - Create a list with initial capacity
...ux
Perhaps you could avoid the list by using a generator instead:
def my_things():
while foo:
#baz
yield bar
#qux
for thing in my_things():
# do something with thing
This way, the list isn't every stored all in memory at all, merely generated as needed.
...
What is the proper way to re-attach detached objects in Hibernate?
...ed transient collection. How can overcome this?
– dma_k
Sep 26 '10 at 21:41
1
...
How to save a PNG image server-side, from a base64 data string
...plode(';', $data);
list(, $data) = explode(',', $data);
$data = base64_decode($data);
file_put_contents('/tmp/image.png', $data);
And as a one-liner:
$data = base64_decode(preg_replace('#^data:image/\w+;base64,#i', '', $data));
An efficient method for extracting, decoding, and checking for e...