大约有 40,000 项符合查询结果（耗时：0.0931秒） [XML]
Stop/Close webcam which is opened by navigator.getUserMedia
I opened a webcam by using the following JavaScript code: navigator.getUserMedia
16 Answers
...
How do you connect to multiple MySQL databases on a single webpage?
...then the last connection created is used (in this case the one represented by $dbh2) e.g.:
mysql_query('select * from tablename');
Other options
If the MySQL user has access to both databases and they are on the same host (i.e. both DBs are accessible from the same connection) you could:
Keep...
LINQ OrderBy versus ThenBy
...
You should definitely use ThenBy rather than multiple OrderBy calls.
I would suggest this:
tmp = invoices.InvoiceCollection
.OrderBy(o => o.InvoiceOwner.LastName)
.ThenBy(o => o.InvoiceOwner.FirstName)
.Th...
Create a matrix of scatterplots (pairs() equivalent) in ggplot2
...
Note: For future reference, the plotmatrix() function has been replaced by the ggpairs() function from the GGally package as @naught101 suggests in another response below to this question.
share
|
...
Rollback a Git merge
...the second most recent state of HEAD, or more technically: "A ref followed by the suffix @ with an ordinal specification enclosed in a brace pair (e.g. {1}, {15}) specifies the n-th prior value of that ref."
– Christopher
Jul 30 '12 at 14:22
...
Parcelable encountered IOException writing serializable object getactivity()
...
Caused by: java.io.NotSerializableException: com.resources.student_list.DSLL$DNode
Your DSLL class appears to have a DNode static inner class, and DNode is not Serializable.
...
Should each and every table have a primary key?
...d allows you to continue along the database normalization path.
As stated by others, there are some reasons not to have a primary key, but most will not be harmed if there is a primary key
share
|
...
Including dependencies in a jar with Maven
...
Why is the name of jar appended by "jar-with-dependencies"?! Any workarounds?
– Tina J
Jan 4 '19 at 17:44
3
...
What is the difference between class and instance methods?
...made.
- (id)init; //instance. Constructs object, increments numberOfPeople by one.
- (int)age; //instance. returns the person age
@end
@implementation MNPerson
- (id)init{
if (self = [super init]){
numberOfPeople++;
age = 0;
}
return self;
}
+ (int)population{
...
Strange, unexpected behavior (disappearing/changing values) when using Hash default value, e.g. Hash
...s a value? Here’s a hint:
h[42] #=> ["a", "b"]
The array returned by each [] call is just the default value, which we’ve been mutating all this time so now contains our new values. Since << doesn’t assign to the hash (there can never be assignment in Ruby without an = present†),...