读取数据库出错，方法或操作未实现

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所以在修复了一个错误后，我得到 studentHelperClass.Form1.cmbBox 由于其保护级别而无法访问我在启动我的程序时遇到了这个错误 Error reading the database, method or操作没有被我的错误标签实现.

So after fixing an error where I was getting studentHelperClass.Form1.cmbBox is inaccessible due to its protection level I got this error when I launched my prorgam Error reading the database, method or operation is not implemented by my error label.

这是我的代码:

public partial class Form1 : Form { MySqlConnection conn; // connection object; string connstring = "server=localhost;user Id=root;database=collegesystem;Convert Zero Datetime=True "; public Form1() { InitializeComponent(); connection(); selectStudent(); } private void selectStudent() { try { studentHelperClass.studentHC.insertMethod(); } catch (Exception err) { lblInfo.Text = " Error reading the database."; lblInfo.Text += err.Message; } }

那是表单的代码，下面是带有方法的类

That is the code for the form, the following is the class with the method

class studentHC : Form1 { public studentHC() { InsertMethod(); } private void InsertMethod() { MySqlConnection conn; // connection object; string connstring = "server=localhost;user Id=root;database=collegesystem;Convert Zero Datetime=True "; conn = new MySqlConnection(connstring); conn.Open(); using (var command = new MySqlCommand("SELECT * FROM person", conn)) { using (var myReader = command.ExecuteReader()) { cmbBox.Items.Add(myReader["personID"]); } } } internal static void insertMethod() { throw new NotImplementedException(); } }

任何输入将不胜感激

好的，所以我摆脱了

internal static void insertMethod() { throw new NotImplementedException(); }

我变了

public studentHC() { InsertMethod(); } private void InsertMethod()

到

public studentHC() { insertMethod(); } private void insertMethod()

现在它说studentHelperClass.studentHC.insertMethod()'由于其保护级别而无法访问

推荐答案

用这个替换你的 studentHC 类

replace your studentHC class with this

class studentHC : Form1 { public studentHC() { InsertMethod(); } public static void InsertMethod() { MySqlConnection conn; // connection object; string connstring = "server=localhost;user Id=root;database=collegesystem;Convert Zero Datetime=True "; conn = new MySqlConnection(connstring); conn.Open(); using (var command = new MySqlCommand("SELECT * FROM person", conn)) { using (var myReader = command.ExecuteReader()) { cmbBox.Items.Add(myReader["personID"]); } } } }

然后替换

studentHelperClass.studentHC.insertMethod();

与

studentHelperClass.studentHC.InsertMethod();