【发布时间】:2016-02-20 12:15:04
【问题描述】:
通过 Visual Studio 学习如何在 ASP.NET 中编写代码有利有弊。优点是一切都可以通过拖放轻松完成,但缺点是我对背后的代码和所有这些“数据绑定”知之甚少。我的 .aspx 页面中有这段代码,但我不确定如何将其“转换”为后面的代码。例如,我现在正在尝试实现一个本质上是可搜索的应用程序(它有一个下拉列表作为要搜索的列的过滤器),具有读取和写入功能的分页。这是我目前在 .aspx 页面中的代码:
<head runat="server">
<title></title>
<style>
.hiddencol
{
display: none;
}
</style>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:TextBox ID="SearchBox" runat="server"></asp:TextBox>
<asp:DropDownList ID="SearchParameterList" runat="server">
<asp:ListItem Selected="True" Value="Project_Name">Project Name</asp:ListItem>
<asp:ListItem Value="Product">Product</asp:ListItem>
<asp:ListItem Value="Description">Description</asp:ListItem>
</asp:DropDownList>
<asp:Button ID="SearchButton" runat="server" Text="Search" OnClick="SearchButton_Click" />
<asp:Button ID="ClearButton" runat="server" OnClick="ClearButton_Click" Text="Clear" />
<br />
<br />
<asp:GridView ID="ProjectTable" runat="server" Font-Names="Verdana,Arial" Font-Size="12px" AutoGenerateColumns="False" AutoGenerateEditButton="True" DataSourceID="PopulateProjectTable" AllowPaging="True" OnPageIndexChanging="ProjectTable_PageIndexChanging>
<AlternatingRowStyle BackColor="#BFE4FF" />
<PagerStyle BorderColor="#CCCCCC" BorderStyle="Solid" BorderWidth="1px" />
<HeaderStyle Height="30px" BackColor="#6DC2FF" Font-Size="12px" BorderColor="#CCCCCC" BorderStyle="Solid" BorderWidth="1px" />
<RowStyle Height="20px" Font-Size="12px" BorderColor="#CCCCCC" BorderStyle="Solid" BorderWidth="1px" />
<Columns>
<asp:BoundField DataField="ProjID" HeaderText="ProjID" ItemStyle-CssClass="hiddencol" HeaderStyle-CssClass="hiddencol" SortExpression="ProjID" />
<asp:BoundField DataField="Project_Name" HeaderText="Project Name Value" ReadOnly="True" SortExpression="Project_Name" />
<asp:BoundField DataField="Product" HeaderText="Product" SortExpression="Product" ReadOnly="True" />
<asp:BoundField DataField="Product_Edit" HeaderText="Product (alternate)" SortExpression="Product_Edit" />
<asp:BoundField DataField="Description" HeaderText="Description" ReadOnly="True" SortExpression="Description" />
<asp:BoundField DataField="Description_Edit" HeaderText="Description (alternate)" SortExpression="Description_Edit" />
<asp:BoundField DataField="Comment" HeaderText="Comment Submission/Approval" SortExpression="Comment" />
</Columns>
</asp:GridView>
<asp:SqlDataSource ID="PopulateProjectTable" runat="server"
ConnectionString="<%$ ConnectionStrings:ODSConnectionString %>"
SelectCommand="SELECT [Project_Name], [Product], [Product_Edit], [Description], [Description_Edit], [Comment], [ProjID] FROM [Pipeline_Detail]"
UpdateCommand="UPDATE [Pipeline_Detail] SET Product_Edit = @Product_Edit, Description_Edit= @Description_Edit, Comment = @Comment WHERE ProjID = @ProjID">
<UpdateParameters>
<asp:Parameter Name="ProjID"/>
<asp:Parameter Name="Product_Edit" Type="String"/>
<asp:Parameter Name="Description_Edit" Type="String"/>
<asp:Parameter Name="Comment" Type="String"/>
</UpdateParameters>
</asp:SqlDataSource>
</div>
</form>
这是我在后面的代码中的内容:
public partial class Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
}
protected void SearchButton_Click(object sender, EventArgs e)
{
PopulateProjectTable.FilterExpression = SearchParameterList.SelectedValue.ToString() + " LIKE " + "'" + "%{0}%" + "'";
}
protected void ClearButton_Click(object sender, EventArgs e)
{
PopulateProjectTable.FilterExpression = "Project_Name LIKE '%%'";
SearchBox.Text = "";
}
}
非常贫瘠。我现在遇到的问题是我搜索后分页“重置”了。例如,如果我搜索无法在一页中显示的内容,它显然会分页。如果我单击不是第 1 页的任何/所有页面,gridview 将重置回其原始选择语句并显示第 2 页的内容。我做了一些研究,发现这是数据绑定方式的问题(如果这不是问题,请随时纠正我)。因此,我该如何解决我现在遇到的问题,是否需要我将我的 .aspx 页面转换为 C# 中的代码?
感谢您的帮助。
编辑:我对背后的代码进行了重大更改:
public partial class Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
}
protected void SearchButton_Click(object sender, EventArgs e)
{
ProjectTable.PageIndex = 0;
ProjectTable.DataSourceID = null;
PopulateProjectTable.SelectCommand = "SELECT [Project_Name], [Product], [Product_Edit], [Description], [Description_Edit], [Comment], [ProjID] FROM [Pipeline_Detail] WHERE " + SearchParameterList.SelectedValue.ToString() + " LIKE '%" + SearchBox.Text + "%'";
ProjectTable.DataSource = PopulateProjectTable;
ProjectTable.DataBind();
}
protected void ClearButton_Click(object sender, EventArgs e)
{
ProjectTable.PageIndex = 0;
ProjectTable.DataSourceID = null;
PopulateProjectTable.SelectCommand = "SELECT [Project_Name], [Product], [Product_Edit], [Description], [Description_Edit], [Comment], [ProjID] FROM [Pipeline_Detail] WHERE Project_Name LIKE '%%'";
ProjectTable.DataSource = PopulateProjectTable;
ProjectTable.DataBind();
SearchBox.Text = "";
}
protected void ProjectTable_PageIndexChanging(object sender, GridViewPageEventArgs e)
{
ProjectTable.PageIndex = e.NewPageIndex;
ProjectTable.DataSourceID = null;
PopulateProjectTable.SelectCommand = "SELECT [Project_Name], [Product], [Product_Edit], [Description], [Description_Edit], [Comment], [ProjID] FROM [Pipeline_Detail] WHERE " + SearchParameterList.SelectedValue.ToString() + " LIKE '%" + SearchBox.Text + "%'" ;
ProjectTable.DataSource = PopulateProjectTable;
ProjectTable.DataBind();
}
}
我现在遇到了这些类型的错误:
The GridView 'ProjectTable' fired event RowEditing which wasn't handled.
The GridView 'ProjectTable' fired event RowCancelingEdit which wasn't handled.
有人知道怎么回事吗?
【问题讨论】:
-
赞成,因为您显然对自己有智慧。如果今晚我下班时没有回答这个问题,我会试一试。我确实认为您的问题可能过于宽泛,无法给出简单的答案。
-
非常感谢您的支持。从来没有上课,所以一切都是自学的。我自己能学到的只有这么多。
-
由于您似乎渴望学习并且在学习过程的开始阶段,您可能希望完全放弃 Web 表单,因为它显然与行业的发展方向不符。改为学习 ASP.NET MVC。
-
有意思,我去看看。不过,我想先完成这个。
-
@mason Webforms 不会去任何地方。
标签: c# asp.net gridview webforms