大约有 40,000 项符合查询结果（耗时：0.0488秒） [XML]
What are dictionary view objects?
...
>>> del dishes['eggs']
>>> keys # No eggs anymore!
dict_keys(['sausage', 'bacon', 'spam'])
>>> values # No eggs value (2) anymore!
dict_values([1, 1, 500])
(The Python 2 equivalent uses dishes.viewkeys() and dishes.viewvalues().)
This example shows the dynamic char...
What's the cause of this FatalExecutionEngineError in .NET 4.5 beta? [closed]
...d .cctor() cil managed
{
// Code size 11 (0xb)
.maxstack 8
IL_0000: ldstr ""
IL_0005: stsfld string System.String::Empty
IL_000a: ret
} // end of method String::.cctor
In the .NET 4.5 version of mscorlib.dll, String.cctor (the static constructor) is conspicuously abse...
Python argparse ignore unrecognised arguments
...
Replace
args = parser.parse_args()
with
args, unknown = parser.parse_known_args()
For example,
import argparse
parser = argparse.ArgumentParser()
parser.add_argument('--foo')
args, unknown = parser.parse_known_args(['--foo', 'BAR', 'spam'])
prin...
Android: upgrading DB version and adding new table
...on't forget your new users!
Don't forget to add
database.execSQL(DATABASE_CREATE_color);
to your onCreate() method as well or newly installed apps will lack the table.
4. How to deal with multiple database changes over time
When you have successive app upgrades, several of which have database...
How can I prevent SQL injection in PHP?
...ction->prepare('SELECT * FROM employees WHERE name = ?');
$stmt->bind_param('s', $name); // 's' specifies the variable type => 'string'
$stmt->execute();
$result = $stmt->get_result();
while ($row = $result->fetch_assoc()) {
// Do something with $row
}
If you're connecting...
Why should eval be avoided in Bash, and what should I use instead?
...than eval if you want to do something more complex:
# Add to scenario:
VAR_2='4 5 6'
# We could use:
local ref="${REF}_2"
echo "${!ref}"
# Versus the bash < 2 method, which might be simpler to those accustomed to eval:
eval "echo \"\$${REF}_2\""
Regardless, the new method is more intuitive, ...
How can jQuery deferred be used?
...he new Deferred object and the attached methods .when , .Deferred and ._Deferred .
11 Answers
...
How do I pass a variable by reference?
...le type
Let's try to modify the list that was passed to a method:
def try_to_change_list_contents(the_list):
print('got', the_list)
the_list.append('four')
print('changed to', the_list)
outer_list = ['one', 'two', 'three']
print('before, outer_list =', outer_list)
try_to_change_list_...
receiver type *** for instance message is a forward declaration
...wered Jan 11 '12 at 6:47
Catfish_ManCatfish_Man
38.6k1111 gold badges6363 silver badges8181 bronze badges
...
How to loop through all the properties of a class?
... given by Brannon:
Public Sub DisplayAll(ByVal Someobject As Foo)
Dim _type As Type = Someobject.GetType()
Dim properties() As PropertyInfo = _type.GetProperties() 'line 3
For Each _property As PropertyInfo In properties
Console.WriteLine("Name: " + _property.Name + ", Value: "...