C# 或 Sql 中常用代码集锦 散分了！！
搜集一些C# 或 Sql 中常用代码集锦，学习学习
[解决办法]
SQL操作全集
http://topic.csdn.net/u/20080515/16/6f359854-5403-4397-89e3-b1b8dd71d527.html
C#通讯编程（整理）|大家可以进来学习
http://topic.csdn.net/u/20080623/08/4bbd2475-45f1-42e3-a613-16b094759ade.html
Asp.NET生成静态页面并分页
http://topic.csdn.net/u/20080624/10/26A45062-572C-47E9-BB38-D9AA05B6C2ED.html
[解决办法]
藏经阁第2卷-SQL常用的函数
http://topic.csdn.net/u/20080803/21/1270777b-a2d6-4323-92d5-cdaa9cf30cf8.html
实现两个数据库中某个表同步(两台服务器)
http://topic.csdn.net/u/20080618/10/4c893d16-47fa-468c-9c39-0f316546d0ac.html
【OpenFlashChart】免费的开源图表项目，图表效果超赞，支持.Net。
http://topic.csdn.net/u/20090115/22/C3F0D94A-8887-462C-A481-E0C910C88FB2.html
国内顶级IT公司面试题，答案
http://topic.csdn.net/u/20090317/18/FBB7DA31-C87E-4FDD-9F15-ECAD63211A35.html
25 个在 Web 中嵌入图表的免费资源
http://topic.csdn.net/u/20090414/10/C8DD7E01-CB11-447E-B79E-CDFC2BF62B89.html
没钱买书的就来下吧 电子书
http://topic.csdn.net/u/20090414/22/38ba0165-1a6d-46ab-99db-4545c0062505.html
[解决办法]
参考
参考
参考
参考
[解决办法]
/* 字符函数 *//* 返回字符表达式中最左侧字符的ASCII代码值 */select Ascii('a') --a:97,A:65/* 将整数ASCII代码转换为字符 */select Char(97)--97:a,65:A/* 返回表达式中指定字符的开始位置 */select Charindex('b','abcdefg',5)/* 以整数返回两个字符表达式的SOUNDEX值之差 */select Difference('bet','bit')--3/* 返回字符表达式最左侧指定数目的字符 */select Left('abcdefg',3)--abc/* 返回给定字符串表达的字符数 */select Len('abcdefg')--7/* 返回将大写字符转换为小字符的字符表达式 */select Lower('ABCDEFG')--abcdefg/* 返回删除了前导空格之后字符表达式 */select Ltrim(' abcdefg')--abcdefg/* 返回具有给定的整数代码的UNICODE字符 */select Nchar(65)--A/* 返回指定表达式中模式第一次出现的开始位置 */select Patindex('%_cd%','abcdefg')--2/* 返回为成为有效的SQL SERVER分隔标识符而添加了分隔符的UNICODE字符串 */select Quotename('create table')/* 用第三个表达式替换第一个表达式中出现的第二个表达式 */select Replace('abcdefg','cd','xxx')--abxxxefg/* 按指定次数重复表达式 */select Replicate('abc|',4)--abc|abc|abc|abc|/* 返回字符表达式的逆向表达式 */select Reverse('abc')--cba/* 返回字符表达式右侧指定数目的字符 */select Right('abcd',3)--bcd/* 返回截断了所有尾随空格之后的字符表达式 */select Rtrim('abcd ')--abcd/* 返回由四个字符表达的SOUNDEX代码 */select Soundex('abcd')--A120/* 返回由重复空格组成的字符串 */select Space(10)--[ ]/* 返回从默认表达转换而来的字符串 */select Str(100)--[ 100]/* */select Str(100,3)--[100]/* */select Str(14.4444,5,4)--[14.44]/* 删除指定长度的字符,并在指定的起点处插入另一组字符 */select Stuff('abcdefg',2,4,'xxx')--axxxfg/* 返回字符表达式,二进制,文本表达式或图像表达的一部分 */select Substring('abcdefg',2,3)--bcd/* 返回表达第一个字符的UNICODE整数值 */select Unicode('a')--97/* 返回将小写字符转换为大写字符的字符表达式 */select Upper('a')--'A'
[解决办法]
//某些时候你或许想 "重复使用" 名为 i 的变量，那么定义 Scope 吧。{ var i = 1;}{ var i = 2;}//类型相同时，和我们一次声明多个同类型变量差不多。using (SqlConnection conn = new SqlConnection(), conn2 = new SqlConnection()){}如果类型不同，那么就写成下面这样。using (MemoryStream stream = new MemoryStream())using (SqlConnection conn = new SqlConnection()){}//大家还可以试试这个 [Condition("DEBUG")] public void YourDebugStuff() { }
[解决办法]
可以坚强勇敢的用来实现串口通信。
using System;
using System.Runtime.InteropServices;
namespace BusApp
{
/// <summary>
///
/// </summary>
public class mycom
{
public mycom()
{
//
// TODO: 在此处添加构造函数逻辑
//
}
public int PortNum; //1,2,3,4
public int BaudRate; //1200,2400,4800,9600
public byte ByteSize; //8 bits
public byte Parity; // 0-4=no,odd,even,mark,space
public byte StopBits; // 0,1,2 = 1, 1.5, 2
public int ReadTimeout; //10
//comm port win32 file handle
private int hComm = -1;
public bool Opened = false;
//win32 api constants
private const uint GENERIC_READ = 0x80000000;
private const uint GENERIC_WRITE = 0x40000000;
private const int OPEN_EXISTING = 3;
private const int INVALID_HANDLE_VALUE = -1;
[StructLayout(LayoutKind.Sequential)]
private struct DCB
{
//taken from c struct in platform sdk
public int DCBlength; // sizeof(DCB)
public int BaudRate; // current baud rate
public int fBinary; // binary mode, no EOF check
public int fParity; // enable parity checking
public int fOutxCtsFlow; // CTS output flow control
public int fOutxDsrFlow; // DSR output flow control
public int fDtrControl; // DTR flow control type
public int fDsrSensitivity; // DSR sensitivity
public int fTXContinueOnXoff; // XOFF continues Tx
public int fOutX; // XON/XOFF out flow control
public int fInX; // XON/XOFF in flow control
public int fErrorChar; // enable error replacement
public int fNull; // enable null stripping
public int fRtsControl; // RTS flow control
public int fAbortOnError; // abort on error
public int fDummy2; // reserved
public ushort wReserved; // not currently used
public ushort XonLim; // transmit XON threshold
public ushort XoffLim; // transmit XOFF threshold
public byte ByteSize; // number of bits/byte, 4-8
public byte Parity; // 0-4=no,odd,even,mark,space
public byte StopBits; // 0,1,2 = 1, 1.5, 2
public char XonChar; // Tx and Rx XON character
public char XoffChar; // Tx and Rx XOFF character
public char ErrorChar; // error replacement character
public char EofChar; // end of input character
public char EvtChar; // received event character
public ushort wReserved1; // reserved; do not use
}
[StructLayout(LayoutKind.Sequential)]
private struct COMMTIMEOUTS
{
public int ReadIntervalTimeout;
public int ReadTotalTimeoutMultiplier;
public int ReadTotalTimeoutConstant;
public int WriteTotalTimeoutMultiplier;
public int WriteTotalTimeoutConstant;
}
[StructLayout(LayoutKind.Sequential)]
private struct OVERLAPPED
{
public int Internal;
public int InternalHigh;
public int Offset;
public int OffsetHigh;
public int hEvent;
}
[DllImport("kernel32.dll")]
private static extern int CreateFile(
string lpFileName, // file name
uint dwDesiredAccess, // access mode
int dwShareMode, // share mode
int lpSecurityAttributes, // SD
int dwCreationDisposition, // how to create
int dwFlagsAndAttributes, // file attributes
int hTemplateFile // handle to template file
);
[DllImport("kernel32.dll")]
private static extern bool GetCommState(
int hFile, // handle to communications device
ref DCB lpDCB // device-control block
);
[DllImport("kernel32.dll")]
private static extern bool BuildCommDCB(
string lpDef, // device-control string
ref DCB lpDCB // device-control block
);
[DllImport("kernel32.dll")]
private static extern bool SetCommState(
int hFile, // handle to communications device
ref DCB lpDCB // device-control block
);
[DllImport("kernel32.dll")]
private static extern bool GetCommTimeouts(
int hFile, // handle to comm device
ref COMMTIMEOUTS lpCommTimeouts // time-out values
);
[DllImport("kernel32.dll")]
private static extern bool SetCommTimeouts(
int hFile, // handle to comm device
ref COMMTIMEOUTS lpCommTimeouts // time-out values
);
[DllImport("kernel32.dll")]
private static extern bool ReadFile(
int hFile, // handle to file
byte[] lpBuffer, // data buffer
int nNumberOfBytesToRead, // number of bytes to read
ref int lpNumberOfBytesRead, // number of bytes read
ref OVERLAPPED lpOverlapped // overlapped buffer
);
[DllImport("kernel32.dll")]
private static extern bool WriteFile(
int hFile, // handle to file
byte[] lpBuffer, // data buffer
int nNumberOfBytesToWrite, // number of bytes to write
ref int lpNumberOfBytesWritten, // number of bytes written
ref OVERLAPPED lpOverlapped // overlapped buffer
);
[DllImport("kernel32.dll")]
private static extern bool CloseHandle(
int hObject // handle to object
);
public void Open()
{
DCB dcbCommPort = new DCB();
COMMTIMEOUTS ctoCommPort = new COMMTIMEOUTS();
// OPEN THE COMM PORT.
hComm = CreateFile("COM" + PortNum ,GENERIC_READ | GENERIC_WRITE,0, 0,OPEN_EXISTING,0,0);
// IF THE PORT CANNOT BE OPENED, BAIL OUT.
if(hComm == INVALID_HANDLE_VALUE)
{
throw(new ApplicationException("Comm Port Can Not Be Opened"));
}
// SET THE COMM TIMEOUTS.
GetCommTimeouts(hComm,ref ctoCommPort);
ctoCommPort.ReadTotalTimeoutConstant = ReadTimeout;
ctoCommPort.ReadTotalTimeoutMultiplier = 0;
ctoCommPort.WriteTotalTimeoutMultiplier = 0;
ctoCommPort.WriteTotalTimeoutConstant = 0;
SetCommTimeouts(hComm,ref ctoCommPort);
// SET BAUD RATE, PARITY, WORD SIZE, AND STOP BITS.
// THERE ARE OTHER WAYS OF DOING SETTING THESE BUT THIS IS THE EASIEST.
// IF YOU WANT TO LATER ADD CODE FOR OTHER BAUD RATES, REMEMBER
// THAT THE ARGUMENT FOR BuildCommDCB MUST BE A POINTER TO A STRING.
// ALSO NOTE THAT BuildCommDCB() DEFAULTS TO NO HANDSHAKING.
dcbCommPort.DCBlength = Marshal.SizeOf(dcbCommPort);
GetCommState(hComm, ref dcbCommPort);
dcbCommPort.BaudRate=BaudRate;
dcbCommPort.Parity=Parity;
dcbCommPort.ByteSize=ByteSize;
dcbCommPort.StopBits=StopBits;
SetCommState(hComm, ref dcbCommPort);
Opened = true;
}
public void Close()
{
if (hComm!=INVALID_HANDLE_VALUE)
{
CloseHandle(hComm);
Opened=false;
}
}
public byte[] Read(int NumBytes)
{
byte[] BufBytes;
byte[] OutBytes;
BufBytes = new byte[NumBytes];
if (hComm!=INVALID_HANDLE_VALUE)
{
OVERLAPPED ovlCommPort = new OVERLAPPED();
int BytesRead=0;
ReadFile(hComm,BufBytes,NumBytes,ref BytesRead,ref ovlCommPort);
OutBytes = new byte[BytesRead];
Array.Copy(BufBytes,OutBytes,BytesRead);
}
else
{
throw(new ApplicationException("Comm Port Not Open"));
}
return OutBytes;
}
public int Write(byte[] WriteBytes)
{
int BytesWritten = 0;
if (hComm!=INVALID_HANDLE_VALUE)
{
OVERLAPPED ovlCommPort = new OVERLAPPED();
WriteFile(hComm,WriteBytes,WriteBytes.Length,ref BytesWritten,ref ovlCommPort);
}
else
{
throw(new ApplicationException("Comm Port Not Open"));
}
return BytesWritten;
}
}
}
[解决办法]
// "uid=sa":连接数据库的用户名为sa. // "password=":连接数据库的验证密码为空.他的别名为"pwd",所以我们可以写为"pwd=". // "initial catalog=Northwind":使用的数据源为"Northwind"这个数据库.他的别名为"Database",本句可以写成"Database=Northwind". // "Server=YourSQLServer":使用名为"YourSQLServer"的服务器.他的别名为"Data Source","Address","Addr". // " Connect Timeout=30":连接超时时间为30秒.(根据情况添加) // PS: // 1.你的SQL Server必须已经设置了需要用户名和密码来登录,否则不能用这样的方式来登录.如果你的SQL Server设置为Windows登录,那么在这里就不需要使用"uid"和"password"这样的方式来登录,而需要使用"Trusted_Connection=SSPI"来进行登录. // 2. 如果使用的是本地数据库且定义了实例名,则可以写为"Server=(local)\实例名";如果是远程服务器,则将"(local)"替换为远程服务器的名称或IP地址. string strConnection = "Trusted_Connection=SSPI;"; strConnection += "database=NTF_Navision_enlistment60;Server=CAIXIATA-6BE823;"; strConnection += "Connect Timeout=30";本文来自CSDN博客，转载请标明出处：http://blog.csdn.net/LCL_data/archive/2009/04/30/4139145.aspx
[解决办法]
/*分页查询*/create PROCEDURE [sp_Page] @PageCurrent int, --要显示的页码 @PageSize int,--每页的大小 @ifelse nvarchar(1000),--返回的字段 @where nvarchar(1000),--条件 @order nvarchar(1000)--排序ASBEGIN BEGIN TRY DECLARE @strSQL nvarchar(500),@strSQLcount nvarchar(500),@countPage int if ISNULL(@PageSize,0)<1 set @PageSize=20 set @strSQL='select * from ( select '+@ifelse+',ROW_NUMBER() OVER('+@order+') as row from '+@where+' ) a where row between '+CONVERT(nvarchar(10), @PageCurrent*@PageSize-@PageSize+1)+' and '+CONVERT(nvarchar(10), @PageCurrent*@PageSize)+'' set @strSQLcount='select count(1) as count from '+@where EXECUTE sp_executesql @strSQL; EXECUTE sp_executesql @strSQLcount; END TRY BEGIN CATCH print ERROR_MESSAGE() END CATCHEND
[解决办法]
---测试数据---if object_id('[pactinfo]') is not null drop table [pactinfo]gocreate table [pactinfo]([ID] int,[pactname] varchar(4))insert [pactinfo]select 1,'正常' union allselect 2,'中国' union allselect 3,'做饭' union allselect 4,'加发'go---引用前辈们的一个函数---create function f_GetPy(@str nvarchar(4000)) returns nvarchar(4000) as begin declare @strlen int,@re nvarchar(4000) declare @t table(chr nchar(1) collate Chinese_PRC_CI_AS,letter nchar(1)) insert into @t(chr,letter) select '吖 ', 'A ' union all select '八 ', 'B ' union all select '嚓 ', 'C ' union all select '咑 ', 'D ' union all select '妸 ', 'E ' union all select '发 ', 'F ' union all select '旮 ', 'G ' union all select '铪 ', 'H ' union all select '丌 ', 'J ' union all select '咔 ', 'K ' union all select '垃 ', 'L ' union all select '嘸 ', 'M ' union all select '拏 ', 'N ' union all select '噢 ', 'O ' union all select '妑 ', 'P ' union all select '七 ', 'Q ' union all select '呥 ', 'R ' union all select '仨 ', 'S ' union all select '他 ', 'T ' union all select '屲 ', 'W ' union all select '夕 ', 'X ' union all select '丫 ', 'Y ' union all select '帀 ', 'Z ' select @strlen=len(@str),@re= ' ' while @strlen> 0 begin select top 1 @re=letter+@re,@strlen=@strlen-1 from @t a where chr <=substring(@str,@strlen,1) order by chr desc if @@rowcount=0 select @re=substring(@str,@strlen,1)+@re,@strlen=@strlen-1 end return(@re) end go---查询---select * from [pactinfo]where left(dbo.f_GetPy(pactname),2)='zf'