紅色的部分報錯：ExecuteReader 要求已打開且可用的 Connection。連接的當前狀態為已關閉。“=”號附近有語法錯誤。
/// <summary>
/// 根據學生ID查詢詳細資訊
/// </summary>
/// <param name="studentId">學生ID</param>
/// <returns></returns>
public Students GetStudentDetail(string studentId)
{
string sql = string.Format("select StudentId, StudentName, Gender, Birthday, AttendanceNO, Stulmage, Age, Phone, StudentAddress,IdentityNO,StudentClass.ClassId, ClassName from Students inner join StudentClass on StudentClass.ClassId=Students.ClassId where StudentId ={0}", studentId);
SqlConnection conn = new SqlConnection(connString);//鏈接到資料庫
SqlCommand cmd = new SqlCommand(sql, conn);//發送命令到資料庫
conn.Open();//打開資料庫連接
SqlDataReader reader = cmd.ExecuteReader(CommandBehavior.CloseConnection);
Students students = new Students();
if (reader.Read())
{
students = new Students()
{
StudentId = Convert.ToInt32(reader["StudentId"]),
StudentName = reader["StudentName"].ToString(),
IdentityNO = reader["IdentityNO"].ToString(),
Gender = reader["Gender"].ToString(),
Birthday = Convert.ToDateTime(reader["Birthday"]),
AttendanceNO = reader["AttendanceNO"].ToString(),
Stulmage = reader["Stulmage"].ToString(),
Age = Convert.ToInt32(reader["Age"]),
Phone = reader["Phone"].ToString(),
StudentAddress = reader["StudentAddress"].ToString(),
ClassId = Convert.ToInt32(reader["ClassId"]),
ClassName = reader["ClassName"].ToString()
};
}
return students;
}
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標籤：C#
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