大约有 45,000 项符合查询结果（耗时：0.0388秒） [XML]
Get a list of distinct values in List
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Notes.Select(x => x.Author).Distinct();
This will return a sequence (IEnumerable<string>) of Author values -- one per unique value.
share
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Undo VS 'Exclude from project'?
...alled "Show All Files". To see this button, make sure that your project is selected in the solution explorer.
Show All Files
When this option is active, the file should be there, just grayed out. Right click it, and select "Include In Project".
Include In Project
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How to reshape data from long to wide format
...mes(df) <- unique(dat1$name)
df
sqldf package:
library(sqldf)
sqldf('SELECT name,
MAX(CASE WHEN numbers = 1 THEN value ELSE NULL END) x1,
MAX(CASE WHEN numbers = 2 THEN value ELSE NULL END) x2,
MAX(CASE WHEN numbers = 3 THEN value ELSE NULL END) x3,
MAX(CASE WHEN numbe...
How to use JNDI DataSource provided by Tomcat in Spring?
..."7200000"
testOnBorrow="true"
validationQuery="select 1"
/>
</GlobalNamingResources>
And reference the JNDI resource from Tomcat's web context.xml like this:
<ResourceLink name="jdbc/DatabaseName"
global="jdbc/DatabaseName"
type="javax...
input type=file show only button
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<input type="file" id="selectedFile" style="display: none;" />
<input type="button" value="Browse..." onclick="document.getElementById('selectedFile').click();" />
This will surely work i have used it in my projects.I hope this helps :)
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Vim delete blank lines
... This will delete all the empty lines(do not contain any white space characters..), but that may not be the unique requirement. Someone may still keep one of the empty line. :%!cat -s may be the choice..
– coanor
Nov 21 '12 at 5:04
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can we use xpath with BeautifulSoup?
...tree.HTMLParser()
tree = etree.parse(response, htmlparser)
tree.xpath(xpathselector)
There is also a dedicated lxml.html() module with additional functionality.
Note that in the above example I passed the response object directly to lxml, as having the parser read directly from the stream is more...
What's the best way to join on the same table twice?
...tiple times or using subqueries etc.
I would just clean things up a bit:
SELECT t.PhoneNumber1, t.PhoneNumber2,
t1.SomeOtherFieldForPhone1, t2.someOtherFieldForPhone2
FROM Table1 t
JOIN Table2 t1 ON t1.PhoneNumber = t.PhoneNumber1
JOIN Table2 t2 ON t2.PhoneNumber = t.PhoneNumber2
What i did:...
Multiple commands on same line
...t use ^J as command separator in a string because it is inserting the NULL character terminating the string. however you can use <CR> = "\n".
– Tinmarino
Aug 10 '17 at 13:24
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Loaded nib but the 'view' outlet was not set
...is is Josh Justice proposal, but in a graphical way (pictures are mine):
Select File owner
On right hand side panel select custom class.
Enter the custom class name
On right hand side panel select oultets
Drag view outlet to view component
Finally the View Controller is instantiated with ...