SQLiteFunction简单不起作用

我试图使用我的C＃和ADO.NET代码中的SQLiteFunction。 谁能说我为什么会遇到这个问题？

System.Data.SQLite.dll中发生未处理的“System.Data.SQLite.SQLiteException”类型的exception附加信息：“DEMOIT”附近的SQLite错误：语法错误

我使用.NET 3.5 x86与SQLite ADO.NET 1.0.65 – 帮助！

public class Program { static void Main( string[ args ) { test(); } public static void test() { SQLiteConnection sqlConn = new SQLiteConnection( "Data Source=TestFoods.db;" ); sqlConn.Open(); SQLiteCommand sqlCmd = new SQLiteCommand( "PRAGMA integrity_check" , sqlConn); sqlCmd.ExecuteNonQuery(); SQLiteFunction.RegisterFunction( typeof(DEMOIT) ); sqlCmd = new SQLiteCommand( "SELECT * FROM Foods Where Foods.Name DEMOIT '$butter' " , sqlConn ); sqlCmd.CommandType = CommandType.Text; SQLiteDataAdapter liteAdapter = new SQLiteDataAdapter( sqlCmd ); DataSet dataSet = new DataSet(); liteAdapter.Fill( dataSet , "Foods" ); } } [SQLiteFunction( Name = "DEMOIT" , Arguments = 1 , FuncType = FunctionType.Scalar )] public class DEMOIT : SQLiteFunction { public override object Invoke( object[] args ) { return Convert.ToString( args[0] ) ; } } 

谢谢！

Answer 1

DEMOIT是一个函数，但您正在使用它，就好像它是一个运算符。 试试这个：

 sqlCmd = new SQLiteCommand( "SELECT * FROM Foods Where Foods.Name = DEMOIT('$butter')" , sqlConn ); 

要么：

 sqlCmd = new SQLiteCommand( "SELECT * FROM Foods Where DEMOIT(Foods.Name) = '$butter'" , sqlConn ); 

来自我的旧项目http://war3share.codeplex.com/的示例：

SQL：

 select replayHash from customData where key='Rating' and String2Int(value) < 8 

码：

 using System.Data.SQLite; namespace War3Share.Client.DAL { [SQLiteFunction(Arguments = 1, FuncType = FunctionType.Scalar, Name = "String2Int")] class String2Int : SQLiteFunction { public override object Invoke(object[] args) { string s = args[0] as string; return int.Parse(s); } } }