大约有 200 项符合查询结果（耗时：0.0212秒） [XML]
- App Inventor 2 中文网 - 清泛IT社区，为创新赋能！
当然可以，它是 app 范围内共享的持久化数据，app 退出后数据也会保留。
更多可参考：https://www.fun123.cn/reference/creative/screen_communication.html#%E5%BE%AE%E6%95%B0%E6%8D%AE%E5%BA%93%E4%BC%A0%E5%80%BC
How to use JavaScript regex over multiple lines?
...orkarounds
Using [^]: fastest
Using [\s\S]: 0.83% slower
Using (.|\r|\n): 96% slower
Using (.|[\r\n]): 96% slower
NB: You can also use [^] but it is deprecated in the below comment.
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What does the git index contain EXACTLY?
...ription adjusts to the recent SHA-256 work.
See commit 8afa50a, commit 0756e61, commit 123712b, commit 5b6422a (15 Aug 2020) by Martin Ågren (none).
(Merged by Junio C Hamano -- gitster -- in commit 74a395c, 19 Aug 2020)
index-format.txt: document SHA-256 index format
Signed-off-by: Martin Ågren
...
RSA Public Key format
... of your RSA PUBLIC KEY structure using grep -v -- ----- | tr -d '\n' | base64 -d | openssl asn1parse -inform DER:
0:d=0 hl=4 l= 266 cons: SEQUENCE
4:d=1 hl=4 l= 257 prim: INTEGER :FB1199FF0733F6E805A4FD3B36CA68E94D7B974621162169C71538A539372E27F3F51DF3B08B2E111C2D6BBF...
Delete rows from a pandas DataFrame based on a conditional expression involving len(string) giving K
...faster than drop:
%%timeit
test = pd.DataFrame({'x': np.random.randn(int(1e6))})
test = test[test.x < 0]
# 54.5 ms ± 2.02 ms per loop (mean ± std. dev. of 7 runs, 10 loops each)
%%timeit
test = pd.DataFrame({'x': np.random.randn(int(1e6))})
test.drop(test[test.x > 0].index, inplace=True)
#...
problem with and :after with CSS in WebKit
...='1.1' height='10px' width='15px'%3E%3Ctext x='0' y='10' fill='gray'%3E%E2%96%BE%3C/text%3E%3C/svg%3E");
background-repeat: no-repeat;
background-size: 1.5EM 1EM;
background-position: right center;
background-clip: border-box;
-moz-background-clip: border-box;
-webkit-backgro...
How to debug Lock wait timeout exceeded on MySQL?
...x 36646234376337652d376630302d303030312d353166322d3431326132346664656366352e6d7033; asc 6db47c7e-7f00-0001-51f2-412a24fdecf5.mp3;; 7: len 21; hex 416e67656c73204e6f7720436f6e666572656e6365; asc Angels Now Conference;; 8: len 34; hex 416e67656c73204e6f7720436f6e666572656e6365204a756c7920392c203230313...
Convert a timedelta to days, hours and minutes
...t to take into account fractions of a second
seconds += td.microseconds / 1e6
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How can I specify the base for Math.log() in JavaScript?
...ion with selective rounding: (Math.round(Math.log(1000) / Math.LN10 * 1e6) / 1e6)
– Shane Daniel
Nov 21 '13 at 5:01
...
Detect if value is number in MySQL
... values ('00.00'),('+1'),('.123'),('-.23e4'),('12.e-5'),('3.5e+6'),('a'),('e6'),('+e0');
select
col1,
col1 + 0 as casted,
col1 REGEXP '^[+-]?[0-9]*([0-9]\\.|[0-9]|\\.[0-9])[0-9]*(e[+-]?[0-9]+)?$' as isNumeric
from myTable;
Result:
col1 | casted | isNumeric
-------|---------|----------
...