大约有 30,000 项符合查询结果（耗时：0.0314秒） [XML]
How to call shell commands from Ruby
...ems.
Here are ways to execute a shell script:
cmd = "echo 'hi'" # Sample string that can be used
Kernel#` , commonly called backticks – `cmd`
This is like many other languages, including Bash, PHP, and Perl.
Returns the result (i.e. standard output) of the shell command.
Docs: http://ruby-...
How do you view ALL text from an ntext or nvarchar(max) in SSMS?
... This worked for me: ``` DECLARE @g geography; ... select Cast(@g.ToString() as xml); ```
– Sergei Zinovyev
Aug 7 '17 at 17:26
...
Or versus OrElse
... the right operand won't even be evaluated (this is useful in cases like:
string a;
//...
if (a is null) or (a = "Hi") //...
to avoid a NullReferenceException throw by the right-hand operand.
I'm sincerely astonished that this (lazy evaluation) isn't the default behaviour of or and and as it is ...
How to create a checkbox with a clickable label?
...:
No need to assign an id to every checkbox (great!).
No need to use the extra attribute in the <label>.
The input's clickable area is also the label's clickable area, so there aren't two separate places to click that can control the checkbox - only one, no matter how far apart the <inpu...
Create an empty object in JavaScript with {} or new Object()?
...can receive a parameter, and depending on that parameter, it will create a string, a number, or just an empty object.
For example: new Object(1), will return a Number. new Object("hello") will return a string, it means that the object constructor can delegate -depending on the parameter- the object...
boost Composite keys - C/C++ - 清泛网 - 专注C/C++及内核技术
...site_key, as shown in the example:
struct phonebook_entry
{
std::string family_name;
std::string given_name;
std::string phone_number;
phonebook_entry(
std::string family_name,
std::string given_name,
std::string phone_number):
family_name(family_name),given_...
“Prevent saving changes that require the table to be re-created” negative effects
... int NOT NULL IDENTITY (1, 1),
ProfileID int NOT NULL,
AddressType char(2) NOT NULL,
ContactText varchar(250) NULL
) ON [PRIMARY]
GO
ALTER TABLE raw.Tmp_Contact SET (LOCK_ESCALATION = TABLE)
GO
SET IDENTITY_INSERT raw.Tmp_Contact ON
GO
IF EXISTS(SELECT * FROM raw.Contact)
EXEC(...
What and where are the stack and heap?
...ate a lot of data.
Responsible for memory leaks.
Example:
int foo()
{
char *pBuffer; //<--nothing allocated yet (excluding the pointer itself, which is allocated here on the stack).
bool b = true; // Allocated on the stack.
if(b)
{
//Create 500 bytes on the stack
char buffer[50...
Does Java support default parameter values?
...ys to simulate default parameters in Java:
Method overloading.
void foo(String a, Integer b) {
//...
}
void foo(String a) {
foo(a, 0); // here, 0 is a default value for b
}
foo("a", 2);
foo("a");
One of the limitations of this approach is that it doesn't work if you have two optional ...
How to split a long regular expression into multiple lines in JavaScript?
...
You could convert it to a string and create the expression by calling new RegExp():
var myRE = new RegExp (['^(([^<>()[\]\\.,;:\\s@\"]+(\\.[^<>(),[\]\\.,;:\\s@\"]+)*)',
'|(\\".+\\"))@((\\[[0-9]{1,3}\\.[0-9]{1,3}\\....