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"类型的异常附加信息:"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 '$butter' " , sqlConn ); sqlCmd.CommandType = CommandType.Text; SQLiteDataAdapter liteAdapter = new SQLiteDataAdapter( sqlCmd ); DataSet dataSet = new DataSet(); liteAdapter.Fill( dataSet , "Foods" ); } } [SQLiteFunction( Name = "DEMOIT" , Arguments = 1 , FuncType = FunctionType.Scalar )] public class DEMOIT : SQLiteFunction { public override object Invoke( object[] args ) { return Convert.ToString( args[0] ) ; } }
谢谢!
DEMOIT是一个函数,但您正在使用它,就好像它是一个运算符.试试这个:
sqlCmd = new SQLiteCommand( "SELECT * FROM Foods Where Foods.Name = DEMOIT('$butter')" , sqlConn );
要么:
sqlCmd = new SQLiteCommand( "SELECT * FROM Foods Where DEMOIT(Foods.Name) = '$butter'" , sqlConn );
我的旧项目http://war3share.codeplex.com/中的示例:
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); } } }