c# - 使用 Dapper 删除 List<T>

Question

使用 Dapper 或 Dapper.SimpleCRUD , 如何从表中删除列表。像这样的东西:

    public static void DeleteList<T>(List<T> listToDelete)
    {
        using (var connection = OpenConnection())
        {
            connection.Delete<T>(listToDelete);
        }
    }

但是当我尝试这样做时，我得到...

The member of type DataModel.MyTable cannot be used as a parameter value

WHERE 子句是唯一的选择吗？

Answer 1

Dapper 不了解您的实体；它不像 Entity Framework 。您需要自己执行 SQL 命令或存储过程。

public static void DeleteList(List<int> idToDelete)
{
    using (IDbConnection conn = new SqlConnection(connString))
    {
        conn.Open();
        foreach (int id in idToDelete)
        {
            conn.Execute(@"DELETE FROM [User] WHERE Id = @Id", new {Id = id});
        }
    }
}

或Execute a Command multiple times

public static void DeleteList(List<int> idToDelete)
{
    using (IDbConnection conn = new SqlConnection(connString))
    {
        conn.Open();
        conn.Execute(@"DELETE FROM [User] WHERE Id = @Id",
            idToDelete.Select(x => new { Id = x }).ToArray());
    }
}