小小工程師

[Regular]判各種常用[正則表示式]

2019-06-02T23:06:00.001-07:00

/^[a-zA-ZüöäÜÖÄß]+$/

=>英文大小寫+德文

/^\d+$/;

=> 正則化檢查數字

/^\w+((-\w+)|(\.\w+))*\@[A-Za-z0-9]+((\.|-)[A-Za-z0-9]+)*\.[A-Za-z]+$/;

=>正則化檢查Email

/^[A-Z0-9]+$/;

=>正則化檢查Email

/^[A-Z\sa-z,-]+$/;

=>正則化僅輸入英文字及[,-]

[LeetCode] Rank Scores

2019-06-02T23:00:00.002-07:00

SELECT m.Score

, Rank

FROM Scores m

JOIN (SELECT Score AS 'Score'

, ROW_NUMBER() OVER(ORDER BY Score DESC) AS RANK

FROM (SELECT DISTINCT Score

from Scores)r) r1

ON m.Score = r1.Score

ORDER BY r1.Rank

Runtime: 1348 ms, faster than 26.61% of MS SQL Server online submissions for Rank Scores.

------------------------------------------------------------------------

似乎不好，但簡單的寫法，歡迎大家流言討論，讓你我更好。

[LeetCode] Exchange Seats

2019-05-13T21:02:00.000-07:00

SELECT m.id

, IFNULL(IF ( ( m.id & 0x1 ) = 1,r1.student, r2.student ),m.student) AS 'Student'

FROM seat m

LEFT JOIN seat r1

ON r1.id = (m.id+1)

LEFT JOIN seat r2

ON r2.id = (m.id-1)

ORDER BY id

Runtime: 166 ms, faster than 58.92% of MySQL online submissions for Exchange Seats.
------------------------------------------------------------------------

似乎不好，但簡單的寫法，歡迎大家流言討論，讓你我更好。

[LeetCode] Robot Return to Origin

2019-05-13T20:58:00.000-07:00

public class Solution

{

public bool JudgeCircle(string moves)

{

var ms = moves.ToArray();

int Y = ms.Count(c => c == 'U') - ms.Count(c => c == 'D');

int X = ms.Count(c => c == 'L') - ms.Count(c => c == 'R');

return X == 0 && Y == 0;

}

Runtime: 108 ms, faster than 9.14% of C# online submissions for Robot Return to Origin.

Memory Usage: 25.8 MB, less than 5.55% of C# online submissions for Robot Return to Origin.

--------------------------------------------------------------------------------------------

似乎不好，但簡單的寫法，歡迎大家流言討論，讓你我更好。

C# DB數字型態對應

2019-05-11T07:55:00.001-07:00

[SQL]

------------------------------------

bigint | -2^63~2^63-1)| 8位元組

------------------------------------

int |(-2^31~2^31-1)| 4位元組

------------------------------------

smallint |(-2^15~2^15-1)| 2位元組

------------------------------------

tinyint |(0~255) | 1位元組

[.netC#]

------------------------------------

Int64 | -2^63~2^63-1)| 8位元組

------------------------------------

Int32 |(-2^31~2^31-1)| 4位元組

------------------------------------

Integer |(-2^31~2^31-1)| 4位元組

------------------------------------

Int16 |(-2^15~2^15-1)| 2位元組

↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓對應↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓

[MS SQL]		[C#]
bit	<=>	bool
tinyint	<=>	byte
smallint	<=>	short、Int16
int	<=>	int、Int32、Integer
bigint	<=>	long、Int32
real	<=>	float
float	<=>	double
money	<=>	decimal
decimal	<=>	decimal
datetime	<=>	DateTime
char	<=>	string
varchar	<=>	string
nchar	<=>	string
nvarchar	<=>	string
text	<=>	string
ntext	<=>	string
image	<=>	byte[]
binary	<=>	byte[]
uniqueidentifier	<=>	Guid

real <=> float

tinyint <=> byte

C# Stream 轉 Bytes

2019-05-11T07:54:00.003-07:00

#region - Stream 轉 Bytes -

/// <summary>

/// Stream 轉 Bytes

/// </summary>

/// <param name="stream"> Stream</param>

/// <returns> Bytes</returns>

public static byte[] StreamToBytes( Stream stream)

{

byte[] bytes = new byte[stream.Length];

stream.Read(bytes, 0, bytes.Length);

stream.Seek(0, SeekOrigin.Begin);

return bytes;

}

#endregion

#region - Bytes 轉 Stream -

/// <summary>

/// Bytes 轉 Stream

/// </summary>

/// <param name="bytes"> Bytes</param>

/// <returns> Stream</returns>

public static Stream BytesToStream( byte[] bytes)

{

return new MemoryStream(bytes);

}

#endregion

MS SQL 目的：用浮點數加減時間換算

2019-05-11T07:54:00.001-07:00

目的：用浮點數加減時間換算，例如：日期時間加上0.5小時

SELECT DATEADD(HOUR, 0.5, CAST('2015/01/01 08:00' AS DATETIME))

執行結果還是一樣 2015/01/01 08:00

SELECT DATEADD(MINUTE, 0.5 * 60, CAST('2015/01/01 08:00' AS DATETIME))

執行結果 2015/01/01 08:30

原因：

DATEADD (datepart , number , date )

參數：number，主要為int型別，0.5轉換int還是0

參考網址

https://msdn.microsoft.com/zh-tw/library/ms186819.aspx

C# 下載檔案 - [檔名亂碼問題]

2019-05-11T07:53:00.001-07:00

http://www.dotblogs.com.tw/siro228/archive/2008/10/13/5665.aspx

context.Response.ContentType = "application/octet-stream";

string filename = HttpUtility.UrlPathEncode("中文檔名.ppt");

context.Response.AddHeader("content-disposition", "attachment; filename=\"" + filename + "\";");

byte[] data = (byte[])dt.Rows[0]["Data"];

context.Response.AddHeader("Content-Length", data.Length.ToString());

context.Response.BinaryWrite(data);

context.Response.End();

由於FireFox不會發生，可加上下面的code避開(請參考資料來源)

if (Request.Browser.Browser == "IE") {

fileName = Server.UrlPathEncode(fileName);

}

C# 檔案對應fiel Content Tyoe

2019-05-11T07:52:00.001-07:00

http://www.dotblogs.com.tw/larrynung/archive/2011/03/24/22049.aspx

private static string GetContentTypeForFileName(string fileName)

{

string ext = System.IO.Path.GetExtension(fileName);

using (Microsoft.Win32.RegistryKey registryKey = Microsoft.Win32.Registry.ClassesRoot.OpenSubKey(ext))

{

if (registryKey == null)

return null;

var value = registryKey.GetValue("Content Type");

return (value == null) ? string.Empty : value.ToString();

}

完整範例如下：

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

namespace ConsoleApplication10

{

class Program

{

static void Main(string[] args)

{

const string file = @"C:\Users\Public\Music\Sample Music\Sleep Away.mp3";

Console.WriteLine(GetContentTypeForFileName(file));

}

private static string GetContentTypeForFileName(string fileName)

{

string ext = System.IO.Path.GetExtension(fileName);

using (Microsoft.Win32.RegistryKey registryKey = Microsoft.Win32.Registry.ClassesRoot.OpenSubKey(ext))

{

if (registryKey == null)

return null;

var value = registryKey.GetValue("Content Type");

return (value == null) ? string.Empty : value.ToString();

}

} }

}

C# 圖片轉換格式(附檔名)

2019-05-11T07:51:00.004-07:00

http://www.iteddie.com/2010/11/c_15.html

/// 要儲存的圖片

/// 品質(0~100)

/// 儲存路徑

private void SaveAsJPEG(Image img, int qulity, string path)

{

EncoderParameters myEncoderParameters = new EncoderParameters(1);

EncoderParameter myEncoderParameter = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, qulity);

myEncoderParameters.Param[0] = myEncoderParameter;

img.Save(path, GetEncoder(ImageFormat.Jpeg), myEncoderParameters);

}

///

/// 取得已安裝的影像 Codec 的相關資訊

///

/// System.Drawing.Imaging.ImageFormat

/// System.Drawing.Imaging.ImageCodeInfo

private ImageCodecInfo GetEncoder(ImageFormat format)

{

ImageCodecInfo[] codecs = ImageCodecInfo.GetImageDecoders();

foreach (ImageCodecInfo codec in codecs)

{

if (codec.FormatID == format.Guid)

{

return codec;

}

return null;

}

C# 在 GDI+ 中發生泛型錯誤

2019-05-11T07:50:00.001-07:00

http://blog.miniasp.com/post/2009/05/A-generic-error-occurred-in-GDI-plus.aspx

解決:

http://stackoverflow.com/questions/15571022/how-to-find-reason-for-generic-gdi-error-when-saving-an-image

(會造成記憶體不足)

-----------------------------------------------------------------------------------------------------

2.使用暫存檔及壓縮jpg層級等級

var tempFilePath = Path .Combine(strSavePath,rows + ".tmp");

file.SaveAs(tempFilePath);

using (var result = new Bitmap(tempFilePath))

{

ImageCodecInfo jgpEncoder = null ;

ImageCodecInfo[] codecs = ImageCodecInfo .GetImageDecoders();

foreach (ImageCodecInfo codec in codecs)

{

if (codec.FormatID == ImageFormat .Jpeg.Guid)

{

jgpEncoder = codec;

}

var myEncoder = Encoder .Quality;

EncoderParameters myEncoderParameters = new EncoderParameters(1);

EncoderParameter myEncoderParameter = new EncoderParameter(myEncoder, 75L);

myEncoderParameters.Param[0] = myEncoderParameter;

result.Save(strSaveAs, jgpEncoder, myEncoderParameters);

}

System.IO. File.Delete(tempFilePath);

C# 刪除路徑中資料夾及檔案

2019-05-11T07:47:00.001-07:00

string strSavePath = Server.MapPath("~/Temp/" );

string[] files = Directory .GetFiles(strSavePath);//中的檔案

string[] dirs = Directory .GetDirectories(strSavePath);//中的目錄

foreach (string file in files)

{

System.IO. File.SetAttributes(file, FileAttributes .Normal);

System.IO. File.Delete(file);

}

foreach (string dir in dirs)

{

Directory.Delete(dir);

}

Directory.Delete(strSavePath, false );

C# 確認國籍身分證

2019-05-11T07:46:00.001-07:00

#region - 確認國籍身分證 -

/// <summary>

/// 確認國籍身分證

/// </summary>

/// <param name="country"> 國別代碼</param>

/// <param name="idno"> 身分證字號 </param>

/// <returns></returns>

public static bool GetCheckIdno( EnumCountry country, string idno)

{

switch (country)

{

case EnumCountry .TW:

if (string .IsNullOrWhiteSpace(idno) == false &&

idno.Length == 10)

{

const string header = "ABCDEFGHJKLMNPQRSTUVXYWZIO";

idno = idno.ToUpper();

var char1 = Left(idno, 1);

var char2 = Right(Left(idno, 2), 1);

var char1No = header.IndexOf(char1, StringComparison .Ordinal) + 10;

if (header.IndexOf(char1, StringComparison .Ordinal) > -1 &&

"12".IndexOf(char2, StringComparison .Ordinal) > -1)

{

#region - 台灣身分證 -

var idValue =

(((char1No / 10) * 1) + ((char1No % 10) * 9)) +

( from s in idno.ToArray().Select((c, index) => new { c, index })

where s.index > 0

select Convert .ToInt16(s.c.ToString()) * ((s.index == 9) ? 1 : (9 - s.index))).Sum();

if (idValue % 10 == 0)

{

return true ;

}

#endregion

}

else if (header.IndexOf(char1, StringComparison.Ordinal) > -1 &&

header.IndexOf(char2, StringComparison.Ordinal) > -1)

{

#region - 台灣居留證 -

var char2No = header.IndexOf(char1, StringComparison .Ordinal) + 10;

var idValue =

(((char1No / 10) * 1) + ((char1No % 10) * 9)) +

(((char2No % 10) * 9) * (9 - 1)) +

( from s in idno.ToArray().Select((c, index) => new { c, index })

where s.index > 1

select Convert .ToInt16(s.c.ToString()) * ((s.index == 9) ? 1 : (9 - s.index))).Sum();

if (idValue % 10 == 0)

{

return true ;

}

#endregion

}

return false ;

default:

return true ;

}

#endregion

C# 檢查DPI

2019-05-11T07:44:00.002-07:00

System.Drawing.Image img = System.Drawing.Image.FromFile(fileName);

//获取此图形的水平分辨率(即水平dpi)（以像素/英寸为单位）

float dpiX = img.HorizontalResolution;

//垂直分辨率

float dpiY = img.VerticalResolution;

小小工程師

[Regular]判各種常用[正則表示式]

[LeetCode] Rank Scores

[LeetCode] Exchange Seats

[LeetCode] Robot Return to Origin

C# DB數字型態 對應

C# Stream 轉 Bytes

MS SQL 目的：用浮點數加減時間換算

C# 下載檔案 - [檔名亂碼問題]

C# 檔案對應fiel Content Tyoe

C# 圖片轉換格式(附檔名)

C# 在 GDI+ 中發生泛型錯誤

C# 刪除路徑中資料夾及檔案

C# 確認國籍身分證

C# 檢查DPI

C# DB數字型態對應