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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...
Copy file or directories recursively in Python
...
I suggest you first call shutil.copytree, and if an exception is thrown, then retry with shutil.copy.
import shutil, errno
def copyanything(src, dst):
try:
shutil.copytree(src, dst)
except OSError as exc: # python >2.5
...
Where does PostgreSQL store the database?
...here the data directory is, use this query.
show data_directory;
To see all the run-time parameters, use
show all;
You can create tablespaces to store database objects in other parts of the filesystem. To see tablespaces, which might not be in that data directory, use this query.
SELECT * FRO...
How do you create different variable names while in a loop? [duplicate]
...can do this is with exec(). For example:
for k in range(5):
exec(f'cat_{k} = k*2')
>>> print(cat_0)
0
>>> print(cat_1)
2
>>> print(cat_2)
4
>>> print(cat_3)
6
>>> print(cat_4)
8
Here I am taking advantage of the handy f string formatting in Pytho...
Cannot run Eclipse; JVM terminated. Exit code=13
...
Okey, I solve it. I just reinstall JDK 64-bit, re-extact eclipse-64bit and edit eclipse.ini again.
– Prince OfThief
Feb 9 '11 at 14:13
...
Co-variant array conversion from x to y may cause run-time exception
...js[0] = new Foo(); // again legal, with runtime exception
In C#, you are allowed to reference an array of objects (in your case, LinkLabels) as an array of a base type (in this case, as an array of Controls). It is also compile time legal to assign another object that is a Control to the array. Th...
Dynamically load a JavaScript file
How can you reliably and dynamically load a JavaScript file? This will can be used to implement a module or component that when 'initialized' the component will dynamically load all needed JavaScript library scripts on demand.
...
C# pattern to prevent an event handler hooked twice [duplicate]
...ution and the best one (considering performance) is:
private EventHandler _foo;
public event EventHandler Foo {
add {
_foo -= value;
_foo += value;
}
remove {
_foo -= value;
}
}
No Linq using required. No need to check for null before cancelling a subscrip...
What are 'closures' in .NET?
...thod and the variable j
[CompilerGenerated]
private sealed class <>c__DisplayClass2
{
public <>c__DisplayClass2();
public void <fillFunc>b__0()
{
Console.Write("{0} ", this.j);
}
public int j;
}
for the function:
static void fillFunc(int count) {
...
What is the aspnet_client folder for under the IIS structure?
...
In addition to what others have said, it's usually created by the aspnet_regiis tool, which can be (re-)run by things like Windows Update/AddRemove Windows components/IIS. So sometimes even if you do delete it, it can come back randomly. There may be a way to stop this ...