【C#】XDocument Descendants() 取不到東西

 string xml = @"<?xml version='1.0' encoding='utf-8'?>
                <ComputerBuildReportRequest xmlns:i='http://www.w3.org/2001/XMLSchema-instance' xmlns='http://schemas.ms.it.oem/digitaldistribution/2010/10'>
                    <Bindings>
                        <Binding>
                            <ProductKeyID>1000000002</ProductKeyID>
                            <HardwareHash>xxx</HardwareHash>
                            <HXSpecifics>
                                <UnitPartNumber>123456-789</UnitPartNumber>
                            </HXSpecifics>
                        </Binding>
                        <Binding>
                            <ProductKeyID>1000000003</ProductKeyID>
                            <HardwareHash>yyy</HardwareHash>
                            <HXSpecifics>
                                <UnitPartNumber>123456-787</UnitPartNumber>
                            </HXSpecifics>
                        </Binding>
                      </Bindings>
                </ComputerBuildReportRequest>";
XDocument doc = XDocument.Parse(xml);
var elements = doc.Descendants("Binding"); // empty

以前就碰過，一直懶得研究 XDocument 到底為什麼有時候會秀逗，直接改用 XmlDocument。 這次碰到非用不可的情況，就藉機深究下。 

【C#】Verify permission of specific directory

Actual verification of read permission to specific directory without opens a stream.

【Powershell】Create task scheduler entry

用 PowerShell 建 scheduler task

【MS-SQL】Can't open .trc file generated by SQLDiag

想直接雙擊打開 SQLDiag 錄的 trc 但會碰到

SQL Server Profiler

Failed to open a file. Access is denied.

的錯誤視窗

【MS-SQL】SQLDiag debug

要跑 SQLDiag 的時候發生錯誤，錄完之後沒產生 trc 檔，cmd 有以下錯誤。
\ Error querying installation path for SQLDIAG on . Function result: 2. Message: The system cannot find the file specified.

【WCF】500 InternalServerError The server encountered an error processing the request. See server logs for more details

Error Status Code: 'InternalServerError'

Details: The server encountered an error processing the request. Please see the server logs for more details.

但 Visual Studio 沒有拋出任何 exception。

【Visual Studio】Unexpected exception Could not load file or assembly '' or one of its dependencies.

Unexpected exception Could not load file or assembly '' or one of its dependencies. 

【C#】Max concurrent tasks

【MS-SQL】Cannot open backup device 'xxx'. Operating system error 5(Access is denied.)

Cannot open backup device 'E:\folder-name\file-name.bak'. Operating system error 5(Access is denied.).

【MS-SQL】Connection pool

Timeout expired. The timeout period elapsed prior to obtaining a connection from the pool. This may have occurred because all pooled connections were in use and max pool size was reached.

【MS-SQL】BACKUP LOG cannot be performed because there is no current database backup

BACKUP LOG cannot be performed because there is no current database backup

不確定是 shrink 還是改 log size 或其他什麼的，突然沒辦法用之前做的 full back 還原。

【MS-SQL】The transaction log for database 'DatabaseName' is full due to 'LOG_BACKUP'

The transaction log for database 'DatabaseName' is full due to 'LOG_BACKUP'

【C#】0x string to byte[] and convert back

MD5 測試用到的

【C#】IProgress

IProgress 是類似輕量化版的 BackgroundWorker

【C#】Various kinds of lock

除了標準的 lock (){} 外，還有對應不同應用的其他鎖

【C#】Interlocked

為多重執行緒共用的變數提供不可部分完成的作業 (Atomic Operation)。

【C#】Task

Task 是抽象化後的緒操作類(from the thread pool)

【C#】Exception handling while multi-threading

【C#】Thread 101

【Dairy】Word multilevel list convex

1.1 xxx
1.2 xxx
...
1.10       xxx
凸一大格的問題