The document discusses several topics related to programming including delegates, using statements, LINQ queries, parsing text files, and preventing SQL injection attacks. Key points covered include how to use delegates to handle variable processing logic, the using statement to ensure objects are disposed properly, comparing text in files using LINQ queries, and protecting against SQL injection by parameterizing queries.

1. 心得分享
李佳駿

2. 委派 delegate
使用時機：可能會碰到某個方法在執行時需要
額外的處理，但你不想／無法將這部份的處理
寫死在類別裡（因為變化太多或無法預先得知
其處理規則）

3. 委派 delegate-1
 void Main()
 {
 CarMileage(10,0).Dump();
 }
 public int CarMileage(int time , int cartype)
 {
 switch (cartype)
 {
 case 0:
 return 10 * time;
 case 1:
 return 20 * time;
 default :
 return 30 * time;
 }
 }


4. 委派 delegate-2
 void Main()
 {
 CarMileage Mileage = new CarMileage(Car0);
 Mileage(10).Dump();
 }
 public delegate int CarMileage(int time);
 public int Car0(int time)
 {
 return 10 * time;
 }
 public int Car1(int time)
 {
 return 20 * time ;
 }
 public int CarOther(int time)
 {
 return 30 * time ;
 }

5. Using()
一些物件在執行完成後需要做 Dispose();
釋放記憶體 ，避免程式撰寫時會遺漏可以利用
 using (ZipArchive archive =
 new ZipArchive(zipToOpen, ZipArchiveMode.Update))
 {
 // 要做的事情
 }

6. ZipFile.OpenRead(zipPath)
number of entries expected in end of central
directory does not correspond to number of entries
in central directory
NuGet :DotNetZip

7. IEnumerable<T>
判斷有無資料請用
 if (resultItem.Count() > 0)
 if (resultItem.Any())

8. 取得 XML 資料
1. doc.Elements("cn-publication).
Element("document-id").Value;
1. doc.Descendants().Where(u => u.Name
== "country").First().Value;

9. SQL 隱碼攻擊
 using (SqlConnection conn = new SqlConnection(connstr))
 {
 conn.Open();
 StringBuilder sqlStr = new StringBuilder(
 @"Select * from [Table] where ID =“ + textBox1.Text );
 cmd.ExecuteNonQuery();
 }

10. SQL 隱碼攻擊 -1
 using (SqlConnection conn = new SqlConnection(connstr))
 {
 conn.Open();
 StringBuilder sqlStr = new StringBuilder(
 @"Select * from [Table] where ID=@ID“);
 SqlCommand cmd = new SqlCommand(sqlStr.ToString(), conn);
 cmd.Parameters.Add(new SqlParameter("@ ID ", textBox.Text));
 cmd.ExecuteNonQuery();
 }

11. .txt 比對資料 -1
比對字串裡面是否有“ 123” 這個字串
string sentence = File.ReadAllText(@"D:log.txt");
var isContain =
sentence.IndexOf("123",
StringComparison.OrdinalIgnoreCase) >= 0;


12. .txt 比對資料 -2
string[] contents = File.ReadAllLines(@“D:Log.txt");
return contents.Any(a => a == “123” );
return contents.All(a => a == “123”);
contents.Where( a=> a.Contains(“123"));

13. LINQ
命名習慣
在 LINQ 文件中，儲存查詢的變數的名稱中都會包含

“query” 這個字； 如果是儲存實際結果的變數，
它們的名稱中就不會有 “ query” 這個字。
var queryCities =
 from city in cities
 where city.Population > 100000
 select city;

14. LINQ-group
 var studentQuery2 =
 from student in students group student by student.Last[0]
 into g orderby g.Key select g;

15. BCP-1
 bcp "SELECT * FROM [table]”
 queryout %CD%FileName.data
 -U username -P password -S server -N
 -N ：當您要傳送的資料包含 ANSI 擴充字元而且您要利用原
生模式的效能時，請使用這個選項。

16. BCP-2
 bcp [DataBase].dbo.[Table]
 in %CD%FileName.data
 -U username -P password -S server –N

17. JavaScript-parseInt()
 >parseInt("123", 10)
 123

 >parseInt("010", 10)
 10
 > parseInt("010")
 8
 > parseInt("hello", 10)
 NaN
 > isNaN(NaN)

18. JavaScript-Boolean()
 false 、 0 、空字串 ("") 、 NaN 、 null 、以及 undefined 都
會成為 false
 > Boolean(234)
 true

19. JavaScript-arguments
 function add() {
 var sum = 0;
 for (var i = 0, j = arguments.length; i < j; i++)
 {
• sum += arguments[i];
 }
 return sum;
 }
 > add(2, 3, 4, 5)
 14
 > add(2, 3, 4)
 9
 arguments.callee.count

20. Jquery
 http://www.w3school.com.cn/tags/att_a_hreflang.asp
 HTML 標籤
 http://jsbin.com/fayidowuce/5/edit
 jsbin

21. Jquery
 <div class="OK"></div>
 $( ".OK" )
 <div id ="OK"></div>
 $( "#OK" )
 <div></div>
 $( "div" )
 <div class="after-andself">
 <p>First Paragraph</p>
 <p>Second Paragraph</p>
 </div>
 $( "div.before-andself" )

22. Jquery
 <div class="left"></div>
 <div class="right"></div>
 $( "div.left, div.right" )

23. SQL 隱碼攻擊 -1
 http://huan-lin.blogspot.com/2009/01/delegate-revisited-csharp-1-to-2-to-3.html 委派
 http://www.dotblogs.com.tw/smartleos/archive/2013/04/10/101297.aspx
 IEnumerable<T> 中有無資料，用 Any()