【发布时间】：2012-11-26 07:35:14
【问题描述】：
我有一个表格，可以带回数据库中的客户列表。还有一个添加客户按钮来添加一个新客户和一个用户可以编辑现有客户的超链接。单击编辑链接时，我可以为该客户恢复正确的数据，但如果我进行更改并单击“更新”按钮，它不会编辑现有数据。另一个问题是重定向添加新客户时也会出现“更新”按钮（用户输入新客户的数据并单击“更新”）。是否可以为不同的操作（添加新或编辑）/查询引用不同的代码？这是我到目前为止所拥有的。感谢您的帮助。
<asp:Content ID="Content1" ContentPlaceHolderID="chpContent" runat="server">
<div>
<h2>Customer Listing</h2>
<br />
</div>
<p style="text-align:center">
<asp:Button ID="btnCustomer" class="button" runat="server" Text="Add New Customer" onclick="btnCustomer_Click" />
</p>
<asp:ListView ID="lv" runat="server"
onselectedindexchanged="lv_SelectedIndexChanged">
<LayoutTemplate>
<table width="110%" class="TableListing">
<tbody>
<thead>
<th width="150">Customer Name</th>
<th width="150">Email</th>
<th width="150">City</th>
<th width="40">State</th>
<th width="110">Phone</th>
<th width="80">Modify</th>
</thead>
<tr id="itemPlaceholder" runat="server"></tr>
</tbody>
</table>
<asp:DataPager ID="ItemDataPager" runat="server" PageSize="20">
<Fields>
<asp:NumericPagerField ButtonCount="5" />
</Fields>
</asp:DataPager>
</LayoutTemplate>
<ItemTemplate>
<tr>
<td><%# Eval ("LastName") %>, <%# Eval ("FirstName") %></td>
<td><%# Eval ("Email") %></td>
<td><%# Eval ("City") %></td>
<td><%# Eval ("State") %></td>
<td><%# Eval ("Phone") %></td>
<td>
<asp:HyperLink ID="lnkEdit" runat="server" NavigateUrl='<%# "CustomerEdit.aspx?ID=" + Eval("CustomerID") %>' Text="Edit" />
</td>
</tr>
</ItemTemplate>
这是我的 CustomerEdit.aspx 页面：
public partial class CustomerEdit : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
this.Master.HighlightNavItem("Customers");
int CustomerID = Int32.Parse(Request.QueryString["ID"]);
//Declare the connection object
SqlConnection Conn = new SqlConnection();
Conn.ConnectionString = ConfigurationManager.ConnectionStrings["MyDatabase"].ConnectionString;
//Connect to the db
Conn.Open();
//Define query
string sql = "SELECT * FROM Customer where CustomerID=@CustomerID";
//Declare the Command
SqlCommand cmd = new SqlCommand(sql, Conn);
//Add the parameters needed for the SQL query
cmd.Parameters.AddWithValue("@CustomerID", CustomerID);
//Declare the DataReader
SqlDataReader dr = null;
//Fill the DataReader
dr = cmd.ExecuteReader();
//Get the data
if (dr.Read() == false)
{
//No Records
dr.Close();
Conn.Close();
return;
}
txtFirstName.Text = dr["FirstName"].ToString();
txtLastName.Text = dr["LastName"].ToString();
txtEmail1.Text = dr["Email"].ToString();
txtEmail2.Text = dr["Email"].ToString();
txtPassword1.Text = dr["Password"].ToString();
txtPassword2.Text = dr["Password"].ToString();
txtAddress1.Text = dr["Address1"].ToString();
txtAddress2.Text = dr["Address2"].ToString();
txtCity.Text = dr["City"].ToString();
txtState.Text = dr["State"].ToString();
txtZip.Text = dr["Zip"].ToString();
txtPhone.Text = dr["Phone"].ToString();
txtFax.Text = dr["Fax"].ToString();
dr.Close();
Conn.Close();
}
protected void btnCancel_Click1(object sender, EventArgs e)
{
Response.Redirect("Customers.aspx");
}
protected void btnUpdate_Click(object sender, EventArgs e)
{
int CustomerID = Int32.Parse(Request.QueryString["ID"]);
//Declare the connection object
SqlConnection Conn = new SqlConnection();
Conn.ConnectionString = ConfigurationManager.ConnectionStrings["MyDatabase"].ConnectionString;
//Connect to the db
Conn.Open();
//Define query
string sql = "UPDATE Customer SET Fax=@Fax Where CustomerID=@CustomerID";
//Declare the Command
SqlCommand cmd = new SqlCommand(sql, Conn);
//Add the parameters needed for the SQL query
cmd.Parameters.AddWithValue("@FirstName", txtFirstName.Text);
cmd.Parameters.AddWithValue("@LastName", txtLastName.Text);
cmd.Parameters.AddWithValue("@Email", txtEmail1.Text);
cmd.Parameters.AddWithValue("@Password", txtPassword1.Text);
cmd.Parameters.AddWithValue("@Address1", txtAddress1.Text);
cmd.Parameters.AddWithValue("@Address2", txtAddress2.Text);
cmd.Parameters.AddWithValue("@City", txtCity.Text);
cmd.Parameters.AddWithValue("@State", txtState.Text);
cmd.Parameters.AddWithValue("@Zip", txtZip.Text);
cmd.Parameters.AddWithValue("@Phone", txtPhone.Text);
cmd.Parameters.AddWithValue("@Fax", txtFax.Text);
//Execute the query
int NumRows = 0;
NumRows = cmd.ExecuteNonQuery();
Conn.Close();
lblUpdate.Text = "Updated " + NumRows.ToString() + " record";
}
}
}
还有我的 Customers.aspx.cs 页面，用户被重定向到该页面。
public partial class Customers : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
this.Master.HighlightNavItem("Customers");
//Declare the connection object
SqlConnection Conn = new SqlConnection();
Conn.ConnectionString = ConfigurationManager.ConnectionStrings["MyDatabase"].ConnectionString;
//Connect to the db
Conn.Open();
//Define query
string sql = "SELECT CustomerID, LastName, FirstName, Email, Password, Address1, Address2, City, State, Zip, Phone, Fax FROM Customer";
//Declare a SQL Adapter
SqlDataAdapter da = new SqlDataAdapter(sql, Conn);
//Declare a DataTable
DataTable dt = new DataTable();
//Populate the DataTable
da.Fill(dt);
//Bind the Listview
lv.DataSource = dt;
lv.DataBind();
dt.Dispose();
da.Dispose();
Conn.Close();
}
protected void btnCustomer_Click(object sender, EventArgs e)
{
Response.Redirect("CustomerEdit.aspx");
}
protected void lv_SelectedIndexChanged(object sender, EventArgs e)
{
Response.Redirect("CustomerEdit.aspx");
}
}
}
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