大约有 43,000 项符合查询结果（耗时：0.0615秒） [XML]
Are string.Equals() and == operator really same? [duplicate]
... most of the time. These methods determine whether two string are the same character-for-character, which is rarely the correct behavior. It is better to use string.Equals(string, StringComparison), which allows you to specify a particular type of comparison. By using the correct comparison, you can...
Is it possible to insert multiple rows at a time in an SQLite database?
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This can be recast into SQLite as:
INSERT INTO 'tablename'
SELECT 'data1' AS 'column1', 'data2' AS 'column2'
UNION ALL SELECT 'data1', 'data2'
UNION ALL SELECT 'data1', 'data2'
UNION ALL SELECT 'data1', 'data2'
a note on performance
I originally used this technique to efficiently lo...
What is a regular expression which will match a valid domain name without a subdomain?
...specs, your specs are wrong. g.co is a valid domain name but g is only one character.
– sch
Apr 24 '12 at 22:23
3
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How enumerate all classes with custom class attribute?
... faster (especially without empirical proof); you've basically written the Select extension method, and the compiler will generate a state machine just as it would if you called Select because of your use of yield return. Finally, any performance gains that might be obtained in the majority of case...
Convert Linq Query Result to Dictionary
... @pawan - that doesn't look right. I'd expect var servers = list.Select( s => new { s.ProjectName, Url = "tcp://" + s.BuildMachineName + ":" + s.PortNumber + "/CruiseManager.rem" } ).ToDictionary( s => s.ProjectName, s.Url ); This creates a dictionary keyed by project name of projec...
Is SQL syntax case sensitive?
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The SQL Keywords are case-insensitive (SELECT, FROM, WHERE, etc), but are often written in all caps. However in some setups table and column names are case-sensitive. MySQL has a configuration option to enable/disable it. Usually case-sensitive table and column na...
Select rows of a matrix that meet a condition
...20, ncol = 4)
colnames(m) <- letters[1:4]
The following command will select the first row of the matrix above.
subset(m, m[,4] == 16)
And this will select the last three.
subset(m, m[,4] > 17)
The result will be a matrix in both cases.
If you want to use column names to select columns...
How to navigate through textfields (Next / Done Buttons)
...m
#import "UITextField+Extended.h"
#import <objc/runtime.h>
static char defaultHashKey;
@implementation UITextField (Extended)
- (UITextField*) nextTextField {
return objc_getAssociatedObject(self, &defaultHashKey);
}
- (void) setNextTextField:(UITextField *)nextTextField{
o...
ORA-00054: resource busy and acquire with NOWAIT specified or timeout expired
...table is already locked by some query. For example, you may have executed "select for update" and have not yet committed/rollbacked and fired another select query. Do a commit/rollback before executing your query.
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ReactJS render string with non-breaking spaces
I have some props that has a string that could contain characters such as &.
It also contains spaces. I want to replace all spaces with &nbsp; .
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