Gridview不显示数据（当我运行程序时，表格是空白的）

Question

请帮我解决这个问题。由于某些原因，我无法在gridview中显示来自我的数据库的表格。每当我运行该程序时，窗体窗体都是空白的（没有任何东西）。

连接管理器类从这里开始：

using System; 
using System.Collections.Generic; 
using System.Data.SqlClient; 
using System.Linq; 
using System.Text; 
using System.Threading.Tasks; 

namespace OCUTutoringSchedule 
{ 
    public class OCUTutoringScheduleDBConn 
    { 
     public static SqlConnection getStringConn() 
     { 
      string connectionString = "Data Source= (LocalDB)\\v11.0;AttachDbFilename=" 
            + "C:\\Users\\Honopac\\Documents\\Visual Studio 2013\\" 
            + "Projects\\OCUTutoringSchedule\\OCUTutoringSchedule\\" 
            + "TutoringSchedule.mdf;Integrated Security=True"; 

     SqlConnection connection = new SqlConnection(connectionString); 

     return connection; 
    } 
} 

}

数据访问类从这里开始：

using System; 
using System.Data; 
using System.Collections.Generic; 
using System.Data.SqlClient; 
using System.Linq; 
using System.Text; 
using System.Threading.Tasks; 
using System.Windows.Forms; 

namespace OCUTutoringSchedule 
{ 
public class TutorDB 
{ 
    public TutorDB() 
    { 

    } 

    public DataTable displayTutor() 
    { 
     DataTable dt = new DataTable("TutorsInformation"); 

     string selectStatement = "SELECT * FROM Employees"; 
     SqlConnection connString = OCUTutoringScheduleDBConn.getStringConn(); 
     connString.Open(); 

     using (SqlCommand cmd = new SqlCommand(selectStatement, connString)) 
     { 
      SqlDataAdapter da = new SqlDataAdapter(cmd); 
      da.Fill(dt);   
     } 
     return dt; 
    } 
}  

}

窗体加载事件从这里开始：

using System; 
using System.Collections.Generic; 
using System.ComponentModel; 
using System.Data; 
using System.Drawing; 
using System.Linq; 
using System.Text; 
using System.Threading.Tasks; 
using System.Windows.Forms; 

namespace OCUTutoringSchedule 
{ 
public partial class Tutoring_Schedule_Maintainace : Form 
{ 
    public Tutoring_Schedule_Maintainace() 
    { 
     InitializeComponent(); 
    } 

    private void Tutoring_Schedule_Maintainace_Load(object sender, EventArgs e) 
    { 
     TutorDB tutorDB = new TutorDB(); 

     DataGridView gv = new DataGridView(); 
     gv.AutoGenerateColumns = true; 
     gv.DataSource = tutorDB.displayTutor(); 
     gv.Visible = true; 

    } 
} 

}

Answer 1

而不是设置gv.Visible到true的，你需要添加gv到Form.Controls Property与this.Controls.Add(gv);。

Answer 2

您并未将datagridview添加到表单中。您可以轻松地使用设计器来做到这一点，而不是自己实例化。

gv.Location = New System.Drawing.Point(10, 55) 
gv.Size() = New System.Drawing.Size(130, 95) 
this.Controls.Add (gv)