它显示没有错误，除非我添加一个记录，它进入捕获异常，这给我连接问题作为输出。我尝试了很多，但无法找到我的错误。这是我的代码：
public partial class Default2 : System.Web.UI.Page
{
private string conStr = WebConfigurationManager.ConnectionStrings["StudentConnectionString1"].ConnectionString;
protected void Page_Load(object sender, EventArgs e)
{
if (!this.IsPostBack)
{
FillList();
BtnsActive(false, true, false, false, false, false);
}
}
protected void BtnsActive(bool a, bool b, bool c, bool d, bool e, bool f)
{
Panel2.Enabled = a;
btnAdd.Enabled = b;
btnInsert.Enabled = c;
btnEdit.Enabled = d;
btnUpdate.Enabled = e;
btnDelete.Enabled = f;
}
protected void FillList()
{
SqlConnection con = new SqlConnection(conStr);
SqlCommand cmd = new SqlCommand("Select * from Student order by StudId", con);
SqlDataReader reader;
DropDownList1.Items.Clear();
try
{
con.Open();
reader = cmd.ExecuteReader();
while (reader.Read())
{
ListItem newItem = new ListItem();
newItem.Text = reader["StudId"] + "," + reader["StudFirstName"];
newItem.Value = reader["StudId"].ToString();
DropDownList1.Items.Add(newItem);
}
}
catch (Exception er)
{
Response.Write("<script language='javascript'>alert('Connection Problem');</script>");
}
finally
{
con.Close();
}
}
protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
{
SqlConnection con = new SqlConnection(conStr);
SqlCommand cmd = new SqlCommand("Select * from Student where StudId='" + DropDownList1.SelectedValue + "'", con);
SqlDataReader reader;
try
{
con.Open();
reader = cmd.ExecuteReader();
reader.Read();
TextBox1.Text = reader["StudId"].ToString();
TextBox2.Text = reader["StudFirstName"].ToString();
CheckBox1.Checked = (bool)reader["Library"];
}
catch (Exception er)
{
Response.Write("<script language='javascript'>alert('Connection Problem');</script>");
}
finally
{
con.Close();
BtnsActive(false, true, false, true, false, true);
}
}
protected void btnAdd_Click(object sender, EventArgs e)
{
BtnsActive(true, false, true, false, false, false);
TextBox1.Text = "";
TextBox2.Text = "";
CheckBox1.Checked = false;
}
protected void btnInsert_Click(object sender, EventArgs e)
{
SqlConnection con = new SqlConnection(conStr);
SqlCommand cmd = new SqlCommand("Insert into Student (StudId,StudFirstName,Library) values(@sid,@name,@library)", con);
cmd.Parameters.AddWithValue("@sid", TextBox1.Text);
cmd.Parameters.AddWithValue("@name", TextBox2.Text);
cmd.Parameters.AddWithValue("@library", CheckBox1.Checked);
try
{
con.Open();
cmd.ExecuteNonQuery();
Response.Write("<script language='javascript'>alert('Record has been added.');</script>");
}
catch (Exception er)
{
Response.Write("<script language='javascript'>alert('Connection Problem');</script>");
}
finally
{
con.Close();
BtnsActive(false, true, false, false, false, false);
FillList();
}
}
protected void btnEdit_Click(object sender, EventArgs e)
{
BtnsActive(true, false, false, false, true, false);
}
protected void btnUpdate_Click(object sender, EventArgs e)
{
SqlConnection con = new SqlConnection(conStr);
SqlCommand cmd = new SqlCommand("Update Student set StudId=@id,StudFirstName=@name,Library=@library) where StudId=@oldId", con);
cmd.Parameters.AddWithValue("@id", TextBox1.Text);
cmd.Parameters.AddWithValue("@name", TextBox2.Text);
cmd.Parameters.AddWithValue("@library", CheckBox1.Checked);
cmd.Parameters.AddWithValue("@oldId", DropDownList1.SelectedValue);
try
{
con.Open();
cmd.ExecuteNonQuery();
Response.Write("<script language='javascript'>alert('The Record has been Updated.');</script>");
}
catch (Exception er)
{
Response.Write("<script language='javascript'>alert('Connection Problem');</script>");
}
finally
{
con.Close();
BtnsActive(false, true, false, false, false, false);
FillList();
}
}
protected void btnDelete_Click(object sender, EventArgs e)
{
SqlConnection con = new SqlConnection(conStr);
SqlCommand cmd = new SqlCommand("Delete from Student where StudId=@id", con);
cmd.Parameters.AddWithValue("@id", TextBox1.Text);
try
{
con.Open();
cmd.ExecuteNonQuery();
Response.Write("<script language='javascript'>alert('The Record has been Deleted.');</script>");
}
catch (Exception er)
{
Response.Write("<script language='javascript'>alert('Connection Problem');</script>");
}
finally
{
con.Close();
BtnsActive(false, true, false, false, false, false);
FillList();
}
}
}
这是我的设计代码很简单..
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default2.aspx.cs" Inherits="Default2" %>
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:Panel ID="Panel1" runat="server" BackColor="#CC3300">
Stud ID:<asp:DropDownList ID="DropDownList1" runat="server" AutoPostBack="True" OnSelectedIndexChanged="DropDownList1_SelectedIndexChanged">
</asp:DropDownList>
<br />
<br />
<asp:Button ID="btnAdd" runat="server" OnClick="btnAdd_Click" Text="Add" />
<asp:Button ID="btnInsert" runat="server" OnClick="btnInsert_Click" Text="Insert" />
<asp:Button ID="btnEdit" runat="server" OnClick="btnEdit_Click" Text="Edit" />
<asp:Button ID="btnUpdate" runat="server" OnClick="btnUpdate_Click" Text="Update" />
<asp:Button ID="btnDelete" runat="server" OnClick="btnDelete_Click" Text="Delete" />
</asp:Panel>
<asp:Panel ID="Panel2" runat="server" BackColor="#FF9933">
<br />
<br />
Stud ID:
<asp:TextBox ID="TextBox1" runat="server" ></asp:TextBox>
<br />
Name:
<asp:TextBox ID="TextBox2" runat="server"></asp:TextBox>
<br />
Library :
<asp:CheckBox ID="CheckBox1" runat="server" />
</asp:Panel>
</div>
</form>
</body>
</html>