大约有 47,000 项符合查询结果（耗时：0.0340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.
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Use LINQ to get items in one List, that are not in another List
...erride the equality:
var excludedIDs = new HashSet<int>(peopleList1.Select(p => p.ID));
var result = peopleList2.Where(p => !excludedIDs.Contains(p.ID));
This variant does not remove duplicates.
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Android emulator doesn't take keyboard input - SDK tools rev 20
...elated note, if your tablet emulator is missing the BACK/HOME buttons, try selecting WXGA800 as the Built-in skin in the AVD editor:
Or by manually setting the skin in config.ini:
skin.name=WXGA800
skin.path=platforms/android-16/skins/WXGA800
(example is for API 16)
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Disabled form fields not submitting data [duplicate]
...entioned: READONLY does not work for <input type='checkbox'> and <select>...</select>.
If you have a Form with disabled checkboxes / selects AND need them to be submitted, you can use jQuery:
$('form').submit(function(e) {
$(':disabled').each(function(e) {
$(this).rem...
C programming in Visual Studio
...project (not for the solution), expand Configuration Properties, C/C++ and select Advanced. Change the Compile As setting to Compile as C Code (/TC).
https://docs.microsoft.com/en-us/cpp/ide/visual-cpp-project-types?view=vs-2017
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Removing fields from struct or hiding them in JSON Response
...ending back to the caller. I'd now like to allow the caller to be able to select the specific fields they would like returned by passing in a "fields" GET parameter.
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Why is the Windows cmd.exe limited to 80 characters wide?
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It isn't. You can right click the title bar, select properties, and in the "Layout" tab alter the screen buffer size (line width and scrollback) and the window size (viewport size). If you started cmd from a shortcut, you can save these settings for future sessions.
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Convert a list of objects to an array of one of the object's properties
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You are looking for
MyList.Select(x=>x.Name).ToArray();
Since Select is an Extension method make sure to add that namespace by adding a
using System.Linq
to your file - then it will show up with Intellisense.
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How do I find which transaction is causing a “Waiting for table metadata lock” state?
...about all the locks transactions are waiting for:
USE INFORMATION_SCHEMA;
SELECT * FROM INNODB_LOCK_WAITS;
A list of blocking transactions:
SELECT *
FROM INNODB_LOCKS
WHERE LOCK_TRX_ID IN (SELECT BLOCKING_TRX_ID FROM INNODB_LOCK_WAITS);
OR
SELECT INNODB_LOCKS.*
FROM INNODB_LOCKS
JOIN INNOD...
Oracle取前N条记录方法 Oracle实现SELECT TOP N的方法 - 数据库(内核) - 清...
Oracle取前N条记录方法 Oracle实现SELECT TOP N的方法select * from ( select * from tablexxx order by xxx desc ) where rownum <= Noracle数据库不支持mysql中limit, top功...select * from ( select * from tablexxx order by xxx desc ) where rownum <= N
oracle数据库不支持mysql中li...