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, int> dayMap = new Dictionary(60); private static readonly int MaxYear = DateTime.Now.Year...= t) { int daysInMonth = DateTime.DaysInMonth(d.Year, d.Month...d.Second, d.Offset); //为此日期应用适当的偏移量 d = new DateTimeOffset(d.DateTime...stoppingToken, string cronExpression, MethodInfo action, object context) { var nextTime = DateTime.Parse...action.Invoke(context, null); }); nextTime = DateTime.Parse
System.Data.SqlClient.SqlCommand $SqlCmd.CommandText = $sql $SqlCmd.Connection = $SqlConn $Reader= $SqlCmd.ExecuteReader...() $DataTable = New-Object System.Data.DataTable $DataTable.Load($Reader) } catch { Write-Warning
一、如要使用SQLite,可以从Visual Studio中的“程序包管理器控制台”输入以下命令完成安装: PM> Install-Package System.Data.SQLite.Core SQLite...二、新建一个SQLite数据库,名称命名为Test.db,其表名称及列定义如下: ?...List tests = new List(); SQLiteDataReader reader = command.ExecuteReader...List tests = new List(); SQLiteDataReader reader = command.ExecuteReader...2)使用ExecuteReader方式比使用Adapter Fill Table方式快一点点,但这不是绝对的,这取决于编写的代码; 3)无论是执行插入或查询操作,使用事务比不使用事务快,尤其是在批量插入操作时
FormatException -12400 e Scientific {0:e} 1.420000e+000 -1.240000e+004 f Fixed point {0:f} 1.42 -12400.00...FormatException x Hexadecimal {0:x4} System....FormatException cf90 Specifier Type Example (Passed System.DateTime.Now) d Short date 10/12/2002 D Long...System.DateTime.Now); // 11:43:34 Console.WriteLine("{0 :f}", System.DateTime.Now);...dd}", System.DateTime.Now); // 27 Console.WriteLine("{0 :ddd}", System.DateTime.Now);
1.42) Output(PassedInt -12400) c Currency {0:c} $1.42 -$12,400 d Decimal (Whole number) {0:d} System.FormatException...1.42 -12400 n Number with commas for thousands {0:n} 1.42 -12,400 r Round trippable {0:r} 1.42 System.FormatException...x Hexadecimal {0:x4} System.FormatException cf90 Specifier Type Example (Passed System.DateTime.Now...("{0 :Y}", System.DateTime.Now); // 2012年3月 Console.WriteLine("{0 :dd}", System.DateTime.Now)...:gggg}", System.DateTime.Now); // 公元 Console.WriteLine("{0 :ggggg}", System.DateTime.Now); //
C#封装的Sqlite访问类,要访问Sqlite这下简单了,直接调用此类中的方法即可 using System; using System.Collections; using System.Collections.Specialized...strSQL">查询语句 /// SQLiteDataReader public static SQLiteDataReader ExecuteReader...); try { connection.Open(); SQLiteDataReader myReader = cmd.ExecuteReader...strSQL">查询语句 /// SQLiteDataReader public static SQLiteDataReader ExecuteReader...PrepareCommand(cmd, connection, null, SQLString, cmdParms); SQLiteDataReader myReader = cmd.ExecuteReader
Getting SQLite to run (the ADO.NET version) under C# 4.0 is a bit tricky....First, download SQLite (the ADO.NET version) from here....Add a reference to the System.Data.SQLite.dll file (located in SQLite.NETbin)....= sql; DataTable dt = new DataTable(); SQLiteDataReader reader = cmd.ExecuteReader...command, connection, cmdText, commandParameters); SQLiteDataReader reader = command.ExecuteReader
importorg.rx.api.dto.common.PagedResponse;importorg.rx.api.dto.common.PagingRequest;importorg.rx.beans.BeanMapper;importorg.rx.beans.DateTime...dataObj.setId(UUID.randomUUID()); }if (dataObj.getCreateTime() == null) { dataObj.setCreateTime(DateTime.now...()); } dataObj.setModifyTime(DateTime.now()); db.store(dataObj);returndataObj; }); } @OverridepublicT...).toList(); } @Overridepublic List listDescending(Predicate condition, FunctionkeySelector) {return executeReader...(condition, keySelector, true);returnpagingParam.page(nQuery); }private NQuery executeReader(Predicate
SQLite这个精巧的小数据库,无需安装软件,只需要一个System.Data.SQLite.DLL文件即可操作SQLite数据库。...SQLite是 一个开源数据库,现在已变得越来越流行,它的体积很小,被广泛应用于各种不同类型的应用中。...System.Text; using System.Web; using System.Configuration; using System.Data; using System.Data.SQLite...commandParameters">传入的参数 /// public static SQLiteDataReader ExecuteReader...PrepareCommand(command, connection, cmdText, p); SQLiteDataReader reader = command.ExecuteReader
/// Sqlite Command parameters....parameter values /// IDataReader public static IDataReader ExecuteReader...== ConnectionState.Closed) cmd.Connection.Open(); IDataReader rdr = cmd.ExecuteReader...coll.Add(parm); break; case ("System.DateTime..."): parm.DbType = DbType.DateTime; parm.ParameterName
System.Data.SQLite数据库通用类 针对对数据库的操作情况,分为以下几种情况: 创建数据库文件; 返回DataTable; 返回DataReader; 执行增删改,返回受影响的行数; 执行查询...,返回第一行第一列(通常用于带有行函数的查询,如SUM/AVG/COUNT等); 返回库中所有的表; 因为在System.Data.SQLite中不存在存储过程,所以所有的操作都是基于文本的SQL语句,...; namespace SQLiteQueryBrowser { /// /// 说明:这是一个针对System.Data.SQLite的数据库常规操作封装的通用类。...执行SQL查询语句所需要的参数,参数必须以它们在SQL语句中的顺序为准 /// public SQLiteDataReader ExecuteReader...command.Parameters.AddRange(parameters); } connection.Open(); return command.ExecuteReader
首先得去网上下载一个叫System.Data.SQLite.dll的文件,要注意64位版本和32位版本是不同的dll,如果下载错了,就会出错 跟添加其他dll一样,先添加此dll的引用 添加命名空间using...System.Data.SQLite; 接下来就是写代码了 string connecString = @"Data Source=D:\SQLite.db;Pooling=true;FailIfMissing...=false"; /D:\sqlite.db就是sqlite数据库所在的目录,它的名字你可以随便改的/ SQLiteConnection conn = new SQLiteConnection..."; //数据库中要事先有个orders表 cmd.CommandType = CommandType.Text; using (SQLiteDataReader reader = cmd.ExecuteReader...reader[0].ToString()); } 用法其实跟平时用C#操作一般的数据库是一样的,另外如果要用到Linq的话得用到另外一个dll文件,System.Data.SQLite.Linq.dll
2、在代码中添加对System.Data.SQLite的引用。在使用SQLite的任何类之前,必须在代码中添加对System.Data.SQLite的引用。...在代码文件的顶部添加以下语句: using System.Data.SQLite; 3、创建一个SQLite数据库文件。...以下是一个创建SQLite数据库的示例代码: SQLiteConnection.CreateFile("MyDatabase.sqlite"); 4、连接到SQLite数据库。...MyTable"; SQLiteCommand command = new SQLiteCommand(sql, connection); SQLiteDataReader reader = command.ExecuteReader...当完成对SQLite数据库的操作时,应该关闭连接。以下是一个关闭SQLite连接的示例代码: connection.Close(); 结语 使用就这么简单。
Access、SQL Server、MySQL、SQLite等常用数据库都支持参数化查询。...(”UserName”, “user01″);cmd.Parameters.AddWithValue(”Password”, “123456″);SqlDataReader reader = cmd.ExecuteReader...string str = ConfigurationManager.ConnectionStrings["sqlserver2008"].ConnectionString; DateTime...txt_username.Text); cnn.Open(); using (SqlDataReader reader = cmd.ExecuteReader...(sqltime); DateTime dt2 = DateTime.Now;
= 1) { throw new FormatException(Environment.GetResourceString("Format_InvalidGuidFormatSpecification...= 'x')) { throw new FormatException(Environment.GetResourceString("Format_InvalidGuidFormatSpecification...3、DateTime类型的字符串输出 因为,不同国家的时间展示不一样,所以DateTime的字符串输出必须使用到IFormatProvider参数 ?...DateTime实现了IFormattable接口,所以它可以自定义地构造我们想要的DateTime字符串,具体实现如下: 第一步: ?...dtfi.ShortTimePattern; case 'u': return dtfi.UniversalSortableDateTimePattern; } throw new FormatException
"; break; case "datetime": csharpType = "DateTime"; break; case "datetime2...); break; case "datetime": commonType = typeof(DateTime); break; case..."datetime2": commonType = typeof(DateTime); break; case "datetimeoffset": commonType...": commonType = "DateTime"; break; case "datetime2": commonType = "DateTime2"; break;...from WITH(NOLOCK) "+Condi; using (SqlDataReader reader = SqlHelper.ExecuteReader
username/password, please try again"); break; } } 4.增删查改的代码(MySqlCommand类、MySqlDataReader类) ExecuteReader...sql= "select * from user"; MySqlCommand cmd = new MySqlCommand(sql,conn); MySqlDataReader reader =cmd.ExecuteReader...();//执行ExecuteReader()返回一个MySqlDataReader对象 while (reader.Read())//初始索引是-1,执行读取下一行数据,返回值是bool { /...(2) 插入、删除、更改 string sql = "insert into user(username,password,registerdate) values('啊宽','123','"+DateTime.Now...+ "-" + DateTime.Now.Month + "-" + DateTime.Now.Day; string sql1= "insert into user(username,password
(); dbDataAdapter.Fill(dataTable); return dataTable; } public DbDataReader ExecuteReader...(DbCommand cmd) { cmd.Connection.Open(); DbDataReader reader = cmd.ExecuteReader(...= db.GetStoredProcCommond("t2_insert"); db.AddInParameter(cmd, "@timeticks", DbType.Int64, DateTime.Now.Ticks...= db.GetStoredProcCommond("t2_insert"); db.AddInParameter(cmd, "@timeticks", DbType.Int64, DateTime.Now.Ticks...= db.GetStoredProcCommond("t2_insert"); db.AddInParameter(cmd, "@timeticks", DbType.Int64, DateTime.Now.Ticks
dependency.OnChange += new OnChangeEventHandler(OnDataChange); using (SqlDataReader reader = command.ExecuteReader...Created_Time DESC", sourceConnection); using (SqlDataReader dataReader = fetchDataCommand.ExecuteReader...Last_Updated_Time DESC", sourceConnection); using (SqlDataReader dataReader = fetchDataCommand.ExecuteReader...string)dataReader["Name"]; decimal value = (decimal)dataReader["Value"]; DateTime...last_updated_time = (DateTime)dataReader["Last_Updated_Time"]; // 更新目标表中的数据
{ public string Id { set; get; } public string Field2A { set; get; } public DateTime...Model1> Field2C { set; get; } } 一、简单操作 1创建文档 //错误写法1.字符串未加引号 /* *“System.FormatException...string json1Right = @"{'Id':'1AAAA1'}"; //错误写法2.集合中的引号嵌套 /* * System.FormatException...} ]}"; //错误写法3 构造键值对时,“:”使用中文输入法 /* * System.FormatException...= filterBuilder.Eq(doc => doc.Field2A, "1") & filterBuilder.Eq(doc => doc.Field2B, DateTime.Parse
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