C＃SQLite插入不工作

Question

我想插入一些数据到一个SQLite文件，但当我尝试这样做没有东西被添加到文件，这是我第一次与SQLite处理，所以不太确定我在做它对。请询问是否需要其他信息。

这里是源代码。

using System; 
using System.Collections.Generic; 
using System.Linq; 
using System.Text; 
using System.Threading.Tasks; 
using System.Windows; 
using System.Windows.Controls; 
using System.Windows.Data; 
using System.Windows.Documents; 
using System.Windows.Input; 
using System.Windows.Media; 
using System.Windows.Media.Imaging; 
using System.Windows.Navigation; 
using System.Windows.Shapes; 
using System.Data.SQLite; 

namespace WpfApplication1 
{ 

    public partial class MainWindow : Window 
    { 
     public MainWindow() 
     { 
      InitializeComponent(); 
      Readlines(); 
     } 

     public void Readlines() 
     { 
      string[] lines = System.IO.File.ReadAllLines(@"D:\Projects\GFKMVC\WpfApplication1\WpfApplication1\Opgave001.txt"); 
      Shift shift = new Shift(); 
      SQLiteConnection.CreateFile("TimePlan.sqlite"); 
      SQLiteConnection dbcon; 
      dbcon = new SQLiteConnection("Data Source=TimePlan.sqlite;Version=3;"); 
      dbcon.Open(); 
      //string DropTable = "DROP DATABASE TimePlane.sqlite"; 
      //SQLiteCommand dropCom = new SQLiteCommand(DropTable, dbcon); 
      //dropCom.ExecuteNonQuery(); 
      string CreateTable = "CREATE TABLE Shifts (EmployeeID INT, Date DATETIME, StartTime DATETIME, EndTime DATETIME, Break INT)"; 
      SQLiteCommand createCom = new SQLiteCommand(CreateTable, dbcon); 
      createCom.ExecuteNonQuery(); 

      foreach (string line in lines) 
      { 
       string[] fields = line.Split(';'); 
       shift.EmployeeID = Int32.Parse(fields[0]); 
       DateTime dt = DateTime.ParseExact(fields[1], "yyyyMMdd", System.Globalization.CultureInfo.InvariantCulture); 
       shift.Date = dt; 
       DateTime st = DateTime.ParseExact(fields[2], "HHmm", System.Globalization.CultureInfo.InvariantCulture); 
       shift.StartTime = st; 
       DateTime et = DateTime.ParseExact(fields[3], "HHmm", System.Globalization.CultureInfo.InvariantCulture); 
       shift.EndTime = et; 
       shift.Break = Int32.Parse(fields[4]); 
       string InsertSql = "INSERT INTO Shifts (EmployeeID, Date, StartTime, EndTime, Break) values ("+shift.EmployeeID+","+shift.StartTime+","+shift.EndTime+","+shift.Break+")"; 
       SQLiteCommand InsertCom = new SQLiteCommand(InsertSql, dbcon); 
       InsertCom.ExecuteNonQuery(); 
      } 
      dbcon.Close(); 
     } 
    } 
} 

Answer 1

参数化查询可以有很大的帮助，避免问题解析输入值（和玩票了解Sql Injection here）

foreach (string line in lines) 
{ 
    string[] fields = line.Split(';'); 
    shift.EmployeeID = Int32.Parse(fields[0]); 
    DateTime dt = DateTime.ParseExact(fields[1], "yyyyMMdd", System.Globalization.CultureInfo.InvariantCulture); 
    shift.Date = dt; 
    DateTime st = DateTime.ParseExact(fields[2], "HHmm", System.Globalization.CultureInfo.InvariantCulture); 
    shift.StartTime = st; 
    DateTime et = DateTime.ParseExact(fields[3], "HHmm", System.Globalization.CultureInfo.InvariantCulture); 
    shift.EndTime = et; 
    shift.Break = Int32.Parse(fields[4]); 
    string InsertSql = @"INSERT INTO Shifts 
         (EmployeeID, Date, StartTime, EndTime, Break) 
         values ($eid, $date, $stime, $etime, $break)"; 

    SQLiteCommand InsertCom = new SQLiteCommand(InsertSql, dbcon); 
    InsertCom.Parameters.Add("$eid", DbType.Int32).Value = shift.EmployeeID; 
    InsertCom.Parameters.Add("$date", DbType.Date).Value = shift.Date ; 
    InsertCom.Parameters.Add("$stime", DbType.Time).Value = shift.StartTime ; 
    InsertCom.Parameters.Add("$etime", DbType.Time).Value = shift.EndTime; 
    InsertCom.Parameters.Add("$break", DbType.Int32).Value = shift.Break; 
    InsertCom.ExecuteNonQuery(); 
} 

这样，工作中的正确格式转换你的价值观数据库引擎所期望的不再是字符串连接格式化规则的手中，而是数据库引擎本身接收日期和时间值并按照它们的喜好使用它们而没有转换错误。

作为一种副产品，您的查询更加清晰并且不易出现错误，例如您错过的错误来传递预期为第二个值的日期。

Answer 2

使用SQLite的

foreach (string line in lines) 
{ 
    string[] fields = line.Split(';'); 
    shift.EmployeeID = Int32.Parse(fields[0]); 
    DateTime dt = DateTime.ParseExact(fields[1], "yyyyMMdd", System.Globalization.CultureInfo.InvariantCulture); 
    shift.Date = dt; 
    DateTime st = DateTime.ParseExact(fields[2], "HHmm", System.Globalization.CultureInfo.InvariantCulture); 
    shift.StartTime = st; 
    DateTime et = DateTime.ParseExact(fields[3], "HHmm", System.Globalization.CultureInfo.InvariantCulture); 
    shift.EndTime = et; 
    shift.Break = Int32.Parse(fields[4]); 

    using (var con = new SQLiteConnection { ConnectionString = "ConnectionString" }) 
    { 
     using (var command = new SQLiteCommand { Connection = con }) 
     { 
      con.Open(); 

      try 
      { 
       command.CommandText = @"INSERT INTO Shifts 
             (EmployeeID, Date, StartTime, EndTime, Break) 
             VALUES (@eid, @date, @stime, @etime, @break)"; 
      command.Parameters.AddWithValue("@eid", shift.EmployeeID); 
      command.Parameters.AddWithValue("@date", shift.Date); 
      command.Parameters.AddWithValue("@stime", shift.StartTime); 
      command.Parameters.AddWithValue("@etime", shift.EndTime); 
      command.Parameters.AddWithValue("@break", shift.Break); 
      command.ExecuteNonQuery(); 
      command.Parameters.Clear(); 
      } 
      catch(SQLiteException ex) 
      { 
       throw ex; 
      } 

     } 
    } 

}