如何在asp.net Web应用程序中搜索数据

Question

I need help with my asp.net web app. I have a page where i display data (all the users) with datagrid. For now, there is no problem when i only have a few users in. But when a database will be populated with 100+ users, it will be difficult to find specified users.

I need to create a search engine (search by name). I already found a few tutorials, but they are all based on creating a new datagrid and creating a new sql data source.

I need to make sure that when admin types in data to find members, it display the searched user in the same datagrid. I already have a code for delete and edit data, can somebody please help me create a code or at least guide me, how to make a search engine? Thank you

Here is my code:

<asp:CommandField CancelText="Cancel" DeleteText="Delete" EditText="Edit" ShowDeleteButton="true" SelectText="Select" UpdateText="Update" ShowEditButton="True" />
        </Columns>
    </asp:GridView>
    <asp:SqlDataSource ID="SqlDataSource" runat="server" ConnectionString="<%$ ConnectionStrings:ConnectionString %>" DeleteCommand="DELETE FROM [Users] WHERE [Id] = @Id" InsertCommand="INSERT INTO [Users] ([Id], [Name], [LastName],) VALUES (@Id, @Name, @LastName,)" SelectCommand="SELECT * FROM [Users]" UpdateCommand="UPDATE [Users] SET [Name] = @Name, [LastName] = @LastName, WHERE [Id] = @Id">
        <DeleteParameters>
            <asp:Parameter Name="Id" Type="Int32" />
        </DeleteParameters>
        <InsertParameters>
            <asp:Parameter Name="Id" Type="Int32" />
            <asp:Parameter Name="Name" Type="String" />
            <asp:Parameter Name="LastName" Type="String" />
        </InsertParameters>
        <UpdateParameters>
            <asp:Parameter Name="Name" Type="String" />
            <asp:Parameter Name="LastName" Type="String" />
        </UpdateParameters>
    </asp:SqlDataSource>

EDIT:

<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" DataKeyNames="Id" DataSourceID="SqlDataSource">
        <Columns>
            <asp:BoundField DataField="Id" HeaderText="Id" ReadOnly="true" SortExpression="Id" Visible="false" />
            <asp:BoundField DataField="name" HeaderText="Name" SortExpression="name" >                    
                <ItemStyle Width="150px" />
            </asp:BoundField>
            <asp:BoundField DataField="lastName" HeaderText="LastName" SortExpression="lastName" >
                <ControlStyle Width="100px" />
                <ItemStyle Width="150px" />
            </asp:BoundField>

Answer 1

As I understand you need to filter by Name the Grid Results. First of all Change your Select query to add a Filter.

SELECT * FROM [Users] where ((not @Name is null and [Name] like '%' + @Name + '%'))

Then add a Control parameter to your SqlDatasource:

<SelectParameters>
<asp:ControlParameter ControlID="TextboxName" Name="Name" PropertyName="Text" ConvertEmptyStringToNull="False" />
</SelectParameters>

Then add to your search button this code behind:

  protected void Button1_Click(object sender, EventArgs e)
    {
        GridView1.DataBind();
    }

Hope it helps you.

Answer 2

Use Filter Expression

Modify your SqlDatasource as

 <asp:SqlDataSource ID="SqlDataSource" runat="server" ConnectionString="<%$ ConnectionStrings:ConnectionString %>" DeleteCommand="DELETE FROM [Users] WHERE [Id] = @Id" InsertCommand="INSERT INTO [Users] ([Id], [Name], [LastName],) VALUES (@Id, @Name, @LastName,)" SelectCommand="SELECT * FROM [Users]" FilterExpression="Name LIKE '%{0}%' UpdateCommand="UPDATE [Users] SET [Name] = @Name, [LastName] = @LastName, WHERE [Id] = @Id">
        <DeleteParameters>
            <asp:Parameter Name="Id" Type="Int32" />
        </DeleteParameters>
        <InsertParameters>
            <asp:Parameter Name="Id" Type="Int32" />
            <asp:Parameter Name="Name" Type="String" />
            <asp:Parameter Name="LastName" Type="String" />
        </InsertParameters>
        <UpdateParameters>
            <asp:Parameter Name="Name" Type="String" />
            <asp:Parameter Name="LastName" Type="String" />
        </UpdateParameters>
<FilterParameters>
                <asp:ControlParameter ControlID="txtSearch" PropertyName="Text" DefaultValue="%" />
            </FilterParameters>
    </asp:SqlDataSource>

Add

FilterExpression="Name LIKE '%{0}%'

AND

<FilterParameters>
   <asp:ControlParameter ControlID="txtSearch" PropertyName="Text" DefaultValue="%" />
</FilterParameters>

Please replace that the txtSearch I used for ControlID with the ID of your textbox which is used for search.

Answer 3

Use backgrid

for avoiding multiple datasources it performs client side filtering and vary fast.