结构化类型必须至少具有一个字段c#

我真正想做的是将字符串数组发送到SQL Server.我正在使用SQL Server 2008.

可以将其标记为重复,但是从stactoverflow实现解决方案时,我面临着另一个问题

链接：How to pass an array into a SQL Server stored procedure

这是我的C#和存储过程代码

C#代码：

string[] str = new string[] {"s" , "a" , "k"};

DataTable dt = new DataTable();
dt.Columns.Add("names");

foreach (string item in str)
{
    dt.Rows.Add(item);
}

foreach (DataRow r in dt.Rows)
{
    Console.WriteLine(r["names"].ToString());
}

DataTable tvp = new DataTable();

SqlConnection conn = new SqlConnection("Data Source=SHZAK;Initial Catalog=synchroniztionTesing;Integrated Security=True");
conn.Open();

using (conn)
{
    SqlCommand cmd = new SqlCommand("strpdPassAnStringArray", conn);
    cmd.CommandType = CommandType.StoredProcedure;

    SqlParameter tvparam = cmd.Parameters.AddWithValue("@List", tvp);
    tvparam.SqlDbType = SqlDbType.Structured;

    cmd.ExecuteScalar();
}

在进行存储过程之前,我创建了一个自定义类型：

CREATE TYPE dbo.arrayOfNames
AS TABLE
(
  name  nvarchar(max)
);

存储过程代码：

CREATE PROCEDURE [dbo].[strpdPassAnStringArray]
      @List AS dbo.arrayOfNames READONLY
AS
BEGIN
    SET NOCOUNT ON;

    SELECT name FROM @List; 
END

但是在应用程序代码中,它引发了这个异常：

There are not enough fields in the Structured type. Structured types must have at least one field.

在线

cmd.ExecuteScalar();

解决方法:

回答：

我很笨拙地问这个问题,但至少现在我知道是什么原因导致了这种异常

感谢@Gusman

如果您的DataTable像我一样是空的,则可以引发此异常

        string[] str = new string[] {"sheraz" , "ahmed" , "khan"};
        DataTable tvp = new DataTable();


        tvp.Columns.Add("names");
        foreach (string item in str)
        {
            tvp.Rows.Add(item);
        }

        foreach (DataRow r in tvp.Rows)
        {
            Console.WriteLine(r["names"].ToString());
        }

        SqlConnection conn = new SqlConnection("Data Source=SHZAK;Initial Catalog=synchroniztionTesing;Integrated Security=True");
        conn.Open();

        using (conn)
        {
            SqlCommand cmd = new SqlCommand("strpdPassAnStringArray", conn);
            cmd.CommandType = CommandType.StoredProcedure;
            SqlParameter tvparam = cmd.Parameters.AddWithValue("@List", tvp);
            tvparam.SqlDbType = SqlDbType.Structured;
            cmd.ExecuteScalar();
        }

标签：table-variable,c,sql-server,stored-procedures
来源： https://codeday.me/bug/20191119/2032528.html