存储过程的返回值仅在ASP.NET中获取第一个字符

using System.Data.SqlClient;

// 创建连接
SqlConnection conn = new SqlConnection("connectionString");

// 创建命令
SqlCommand cmd = new SqlCommand("storedProcedureName", conn);
cmd.CommandType = CommandType.StoredProcedure;

// 添加输出参数
SqlParameter outputParam = new SqlParameter();
outputParam.ParameterName = "@outputParamName";
outputParam.SqlDbType = SqlDbType.VarChar;
outputParam.Direction = ParameterDirection.Output;
outputParam.Size = 50;
cmd.Parameters.Add(outputParam);

// 添加返回值参数
SqlParameter returnParam = new SqlParameter();
returnParam.ParameterName = "@returnParamName";
returnParam.SqlDbType = SqlDbType.Int;
returnParam.Direction = ParameterDirection.ReturnValue;
cmd.Parameters.Add(returnParam);

// 执行存储过程
conn.Open();
cmd.ExecuteNonQuery();

// 获取输出参数和返回值
string outputValue = (string)cmd.Parameters["@outputParamName"].Value;
int returnValue = (int)cmd.Parameters["@returnParamName"].Value;

// 关闭连接
conn.Close();