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Add a property to a JavaScript object using a variable as the name?
...out modifying but it's referenced by other questions that are about dynamically creating objects and so I ended up here and happily benefited from this answer.
– Oliver Lloyd
Oct 29 '16 at 17:40
...
html select option separator
...on>First</option>
</optgroup>
<optgroup label="_________">
<option>Second</option>
<option>Third</option>
</optgroup>
</select>
disabled option (a bit better):
<select>
<option>Fir...
Display names of all constraints for a table in Oracle SQL
...
You need to query the data dictionary, specifically the USER_CONS_COLUMNS view to see the table columns and corresponding constraints:
SELECT *
FROM user_cons_columns
WHERE table_name = '<your table name>';
FYI, unless you specifically created your table with ...
How to get the system uptime in Windows? [closed]
...and line utility checks and displays various system statistics such as installation date, installed hotfixes and more.
Open a Command Prompt and type the following command:
systeminfo
You can also narrow down the results to just the line you need:
systeminfo | find "System Boot Time:"
3: By ...
How to convert list of tuples to multiple lists?
...
xs, ys = [x for x, y in zs], [y for x, y in zs]
return xs, ys
if __name__ == '__main__':
from timeit import timeit
setup_string='''\
N = 2000000
xs = list(range(1, N))
ys = list(range(N+1, N*2))
zs = list(zip(xs, ys))
from __main__ import t1, t2, t3
'''
print(f'zip:\t\t{timeit(...
How do you remove duplicates from a list whilst preserving order?
...n seen or seen_add(x))]
Why assign seen.add to seen_add instead of just calling seen.add? Python is a dynamic language, and resolving seen.add each iteration is more costly than resolving a local variable. seen.add could have changed between iterations, and the runtime isn't smart enough to rule t...
Reading binary file and looping over each byte
...hile byte != "":
# Do stuff with byte.
byte = f.read(1)
finally:
f.close()
Python 2.5-2.7
with open("myfile", "rb") as f:
byte = f.read(1)
while byte != "":
# Do stuff with byte.
byte = f.read(1)
Note that the with statement is not available in versio...
How to base64 encode image in linux bash / shell
...
You need to use cat to get the contents of the file named 'DSC_0251.JPG', rather than the filename itself.
test="$(cat DSC_0251.JPG | base64)"
However, base64 can read from the file itself:
test=$( base64 DSC_0251.JPG )
...
Is it possible to use getters/setters in interface definition?
At the moment, TypeScript does not allow use get/set methods(accessors) in interfaces.
For example:
4 Answers
...
UCenter实现各系统通信的原理 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...原理
1、用户登录bbs，通过logging.php文件中，使用函数uc_user_login验证，如果验证成功，将调用函数uc_user_synlogin（位于uc_client下的client.php文件中）， 在这个函数中调用 uc_api_post('user', 'synlogin', array('uid'=>$uid));之后向UC_API.'/index.php'...