C＃从PostgreSQL检索_text类型 [英] c# retrieve _text type from postgresql

问题描述

我有一个数组，例如[[ 64， 0， 0]，[ 64， 7， 95]，[ 61， 28， 165] ，[ 60， 45， 200]]中的[我从Rails中的ruby中存储，我想在我的C＃项目中检索它。当我这样做时：

I have a array like [["64", "0", "0"], ["64", "7", "95"], ["61", "28", "165"], ["60", "45", "200"]] in Postgres column which I stored from ruby on rails, and I want to retrieve it in my C# project. When I do this:

NpgsqlDataReader reader = command.ExecuteReader();
            DataTable dt = new DataTable();
            while (reader.Read())
            {
                Console.WriteLine("{0}\t{1}", reader.GetName(0), reader.GetString(1));
            }

我遇到以下异常：

System.InvalidCastException: Can't cast database type _text to String

如何获取此列值作为数组
但是当我这样做时：

How can I get this column value as an Array But when I do:

dt.Load(reader);

            foreach (DataRow row in dt.Rows)
            {

                var points = row["points"];
                var json = new JavaScriptSerializer().Serialize(points);
                Console.WriteLine(json);

            }

它返回[ 64， 0， 0， 64， 7， 95， 61， 28， 165， 60， 45， 200]这不是我想要的

it returns ["64","0","0","64","7","95","61","28","165","60","45","200"] which is not what I want

推荐答案

请尝试：

string[,] result = row["points"] as string[,]; 

pgSql已定义了数组字段，因此无法直接转换为字符串。

pgSql has an array field defined, so it cannot convert to string directly.

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