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Cannot set some HTTP headers when using System.Net.WebRequest
... Message without giving a solution to the problem.
– 000
Dec 9 '11 at 2:11
11
Solution is to chec...
Comparing date part only without comparing time in JavaScript
...etHours(0,0,0,0); console.log(t.toJSON()); will print "2016-02-28T15:00:00.000Z", date 28, but not 29 My current time zone is Asia/Tokyo
– transang
Feb 29 '16 at 2:43
9
...
Count(*) vs Count(1) - SQL Server
...utation intensive function.
In my test database, t_even is a table with 1,000,000 rows
This query:
SELECT COUNT(SYS_GUID())
FROM t_even
runs for 48 seconds, since the function needs to evaluate each SYS_GUID() returned to make sure it's not a NULL.
However, this query:
SELECT COUNT(*)
FR...
How to calculate time in hours between two dates in iOS
...se who use swift 3 and above,
let dateString1 = "2018-03-15T14:20:00.000Z"
let dateString2 = "2018-03-20T14:20:00.000Z"
let Dateformatter = DateFormatter()
Dateformatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSSZ"
let date1 = Dateformatter.date(from: dateString1)
let date2 ...
Do sealed classes really offer performance Benefits?
...Release build configuration) emits identical MSIL, which is as follows:
L_0000: newobj instance void <NormalClass or SealedClass>::.ctor()
L_0005: stloc.0
L_0006: ldloc.0
L_0007: ldstr "a string"
L_000c: callvirt instance void <NormalClass or SealedClass>::WriteIt(string)
L_0011: ret ...
MIN/MAX vs ORDER BY and LIMIT
...s data point, MIN() took .36s while SORT and LIMIT took .84s against a 106,000 row table on my dev server.
If, however, you're looking at an indexed column, the difference is harder to notice (meaningless data point is 0.00s in both cases). Looking at the output of explain, however, it looks like ...
Are string.Equals() and == operator really same? [duplicate]
...e happens to frequently use strings containing a particular sequence of 32,000 characters, interning the string may save 64K for each copy that would otherwise be created. But if one interns a 32,000 character string and never again uses that sequence of characters, one will permanently waste 64K o...
Send string to stdin
...y
xxd -r -p <<BINARY | iconv -f UCS-4BE -t UTF-8 | /my/bash/script
0000 79c1 0000 306f 0000 3061 0000 3093 0000 3077 0000 3093 0000 304b 0000 3093 0000 3077 0000 3093 0000 306a 0000 8a71 0000 306b 0000 30ca 0000 30f3 0000 30bb
0000 30f3 0000 30b9 0000 3092 0000 7ffb 0000 8a33 0000 3059 0000 ...
How to replace a character by a newline in Vim
...wq
(echo 'After:'; xxd test) >> output.txt
more output.txt
Before:
0000000: 6261 720a bar.
After:
0000000: 000a 720a ..r.
In other words, \n has inserted the byte 0x00 into the text; \r has inserted the byte 0x0a.
...
C语言结构体里的成员数组和指针 - c++1y / stl - 清泛IT社区，为创新赋能！
...到：# t实例中的p就是一个野指针
(gdb) p t
$1 = {i = 0, c = 0 '\000', d = 0 '\000', p = 0x4003e0 "1\355I\211\..."}
# 输出t的地址
(gdb) p &t
$2 = (struct test *) 0x7fffffffe5f0
#输出(t.i)的地址
(gdb) p &(t.i)
$3 = (char **) 0x7fffffffe5f0
#输出(t.p)的...