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Assign null to a SqlParameter
... for the ?: operator that explains the problem
Either the type of first_expression and second_expression must be the same, or an implicit conversion must exist from one type to the other.
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How would you implement an LRU cache in Java?
...y at the back of the iteration order regardless of whether that entry initially exists in the cache)
– Pacerier
Feb 23 '12 at 18:26
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Create a folder inside documents folder in iOS apps
...NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0]; // Get documents folder
NSString *dataPath = [documentsDirectory stringByAppendingPathComponent:@"/MyFolder"];
if (![[NSFileManager defaultManager] fileExistsAtPath:dataPath])
[[NSFileManager defaultManager] create...
top命令使用详解 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...眠状态
R=运行
S=睡眠
T=跟踪/停止
Z=僵尸进程
x
COMMAND
命令名/命令行
y
WCHAN
若该进程在睡眠，则显示睡眠中的系统函数名
z
Flags
任务标志，参考 sched.h
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top命...
Check if instance is of a type
...wo different meanings.
If you want to check whether an instance is of an exact type then
if (c.GetType() == typeof(TForm))
is the way to go.
If you want to know whether c is an instance of TForm or a subclass then use is/as:
if (c is TForm)
or
TForm form = c as TForm;
if (form != null)
It...
Produce a random number in a range using C#
...
You can try
Random r = new Random();
int rInt = r.Next(0, 100); //for ints
int range = 100;
double rDouble = r.NextDouble()* range; //for doubles
Have a look at
Random Class, Random.Next Method (Int32, Int32) and Random.NextDouble Method
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psql: FATAL: role “postgres” does not exist
... which will just use the latest version.
start postgres server manually: pg_ctl -D /usr/local/var/postgres start
To start server at startup
mkdir -p ~/Library/LaunchAgents
ln -sfv /usr/local/opt/postgresql/*.plist ~/Library/LaunchAgents
launchctl load ~/Library/LaunchAgents/homebrew.mxcl.post...
Flask vs webapp2 for Google App Engine
...easily avoid it. Moreover, despite the fact I sympathize with Flask, I'm really impressed with webapp2 and have my hands itching to try it out. Thank you for answer and for webapp2!
– Anton Moiseev
Jul 22 '11 at 9:52
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Can a local variable's memory be accessed outside its scope?
...said that if you leave stuff behind, they'll shred it for you. If you illegally re-enter your room with a stolen key to get it back, the hotel security staff is not required to catch you sneaking in. You didn't make a contract with them that said "if I try to sneak back into my room later, you are r...
Cannot find module cv2 when using OpenCV
...conda install -c https://conda.binstar.org/menpo opencv
if you are on linux you can do :
pip install opencv-python
or
conda install opencv
Link1 Link2
For python3.5+ check these links : Link3 , Link4
Update:
if you use anaconda, you may simply use this as well (and hence don't need to add menpo ...