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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...
What are the details of “Objective-C Literals” mentioned in the Xcode 4.4 release notes?
...
This part is new. Expression Literals
When you have an expression (M_PI / 16 for example) you should put it inside parenthesis.
This syntax works for numeral expressions, booleans, finding an index in a (C-) string, boolean values, enum constants, and even character strings!
NSNumber *piO...
How can I print the contents of a hash in Perl?
...
Easy:
print "$_ $h{$_}\n" for (keys %h);
Elegant, but actually 30% slower (!):
while (my ($k,$v)=each %h){print "$k $v\n"}
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im...
Some built-in to pad a list in python
...
a += [''] * (N - len(a))
or if you don't want to change a in place
new_a = a + [''] * (N - len(a))
you can always create a subclass of list and call the method whatever you please
class MyList(list):
def ljust(self, n, fillvalue=''):
return self + [fillvalue] * (n - len(self))
a...
TypeError: 'NoneType' object is not iterable in Python
...r a variable containing None. The operation was performed by invoking the __iter__ method on the None.
None has no __iter__ method defined, so Python's virtual machine tells you what it sees: that NoneType has no __iter__ method.
This is why Python's duck-typing ideology is considered bad. The...
How to access session variables from any class in ASP.NET?
I have created a class file in the App_Code folder in my application. I have a session variable
7 Answers
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Perform commands over ssh with Python
...o.SSHClient()
ssh.connect(server, username=username, password=password)
ssh_stdin, ssh_stdout, ssh_stderr = ssh.exec_command(cmd_to_execute)
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fo...
Calculating frames per second in a game
... like float weightRatio = 0.1; and time = time * (1.0 - weightRatio) + last_frame * weightRatio
– korona
Nov 11 '08 at 10:04
2
...
“x not in y” or “not x in y”
...am' not in 'spam and eggs'
>>> dis.dis(notin)
2 0 LOAD_CONST 1 ('ham')
3 LOAD_CONST 2 ('spam and eggs')
6 COMPARE_OP 7 (not in)
9 POP_TOP
10 LOAD_CONST 0 (...
Can comments be used in JSON?
...hen it will be data too.
You could have a designated data element called "_comment" (or something) that would be ignored by apps that use the JSON data.
You would probably be better having the comment in the processes that generates/receives the JSON, as they are supposed to know what the JSON dat...