public static class StaticClass
{
/// <summary>
/// 批量刪除
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="table"></param>
/// <param name="predicate"></param>
/// <returns></returns>
public static int Delete<T>( this Table<T> table, Expression<Func<T, bool >> predicate) where T : class
{
string tableName = table.Context.Mapping.GetTable( typeof (T)).TableName;
DbCommand command=table.Context.GetCommand(table.Where(predicate));
string sqlCondition = command.CommandText;
sqlCondition = sqlCondition.Substring(sqlCondition.LastIndexOf( " WHERE " , StringComparison.InvariantCultureIgnoreCase) + 6 );
// 去掉表中出現的 t0
sqlCondition = sqlCondition.Replace( " [t0]. " , "" );
string commandText = string .Format( " Delete FROM {0} WHERE {1} " , tableName , sqlCondition);
command.CommandText = commandText;
// 執行
try
{
if (command.Connection.State != ConnectionState.Open)
{
command.Connection.Open();
}
return command.ExecuteNonQuery();
}
finally
{
command.Connection.Close();
command.Dispose();
}
}
/// <summary>
/// 批量更新
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="table"></param>
/// <param name="predicate"> 查詢條件表達式 </param>
/// <param name="updater"> 更新表達式 </param>
/// <returns> 影響的行數 </returns>
public static int Update<T>( this Table<T> table, Expression<Func<T, bool >> predicate, Expression<Func<T, T>> updateExp) where T : class
{
string tableName = table.Context.Mapping.GetTable( typeof (T)).TableName;
DbCommand command = table.Context.GetCommand(table.Where(predicate));
string sqlCondition = command.CommandText;
sqlCondition = sqlCondition.Substring(sqlCondition.LastIndexOf( " WHERE " , StringComparison.InvariantCultureIgnoreCase) + 6 );
// 獲取Update的賦值語句
var updateMemberExp = (MemberInitExpression)updateExp.Body;
var updateMemberCollection = updateMemberExp.Bindings.Cast<MemberAssignment>().Select(c =>
{
var p = command.CreateParameter();
p.ParameterName = c.Member.Name;
p.Value = ((ConstantExpression)c.Expression).Value;
return p;
}).ToArray();
string sqlUpdateBlock = string .Join( " , " , updateMemberCollection.Select(c => string .Format( " [{0}]=@{0} " , c.ParameterName)).ToArray());
// 組合SQL 語句
string commandText = string .Format( " UPDATE {0} SET {1} FROM {0} AS t0 WHERE {2} " , tableName, sqlUpdateBlock, sqlCondition);
// 獲取參數數組
command.Parameters.AddRange(updateMemberCollection);
command.CommandText = commandText;
// 執行
try
{
if (command.Connection.State != ConnectionState.Open)
{
command.Connection.Open();
}
return command.ExecuteNonQuery();
}
finally
{
command.Connection.Close();
command.Dispose();
}
}
}
// 查詢
????????? DataClasses1DataContext dbo = new DataClasses1DataContext();
??????????? Table<K_Menu> tb = dbo.GetTable<K_Menu>();
??????????? List<K_MenuCopy> list;//= new List<K_Menu>();
??????????? using (DbConnection dbCon = tb.Context.Connection)
??????????? {
??????????????? var query1 = tb.Select(a => new { a.BigImage, a.Image, a.MenuID });
??????????????? DbCommand dbCommand = tb.Context.GetCommand(query1);
??????????????? dbCon.Open();
??????????????? using (DbDataReader dr = dbCommand.ExecuteReader(CommandBehavior.CloseConnection))
??????????????? {
??????????????????? list = dbo.Translate<K_MenuCopy>(dr).ToList();
??????????????? }
??????????? }
?
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