Append Query String Parameter Values in URL (Parameter pass From Hyperlink which bind in Datalist)

If you are filtering the Data on the same page then refer this.

HTML

<asp:DataList ID="dlFruits" runat="server">
    <ItemTemplate>
        <asp:LinkButton ID="lnkApple" Text="Apple" CommandArgument='<%# Eval("AppleTypeId") %>'
            OnClick="AppleClick" runat="server" />
        <br />
        <asp:LinkButton ID="lnkBanana" Text="Banana" CommandArgument='<%# Eval("BananaTypeId") %>'
            OnClick="BananaClick" runat="server" />
        <br />
        <asp:LinkButton ID="lnkMango" Text="Mango" CommandArgument='<%# Eval("MangoTypeId") %>'
            OnClick="MangoClick" runat="server" />
        <br />
    </ItemTemplate>
    <SeparatorTemplate>
        <hr />
    </SeparatorTemplate>
</asp:DataList>

C#

protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {
        DataTable dt = new DataTable();
        dt.Columns.AddRange(new DataColumn[3] { new DataColumn("AppleTypeId",typeof(int)),
                                                new DataColumn("BananaTypeId",typeof(int)),
                                                new DataColumn("MangoTypeId",typeof(int))});
        dt.Rows.Add(10, 15, 17);
        dt.Rows.Add(18, 85, 35);
        dt.Rows.Add(5, 55, 11);
        this.dlFruits.DataSource = dt;
        this.dlFruits.DataBind();
    }
}
protected void AppleClick(object sender, EventArgs e)
{
    LinkButton lnkApple = sender as LinkButton;
    if (Request.Url.AbsoluteUri.Split('&').Length < 3)
    {
        if (Request.Url.AbsoluteUri.Contains('?'))
        {
            Response.Redirect(Request.Url.AbsoluteUri + "&Apple=" + lnkApple.CommandArgument);
        }
        else
        {
            Response.Redirect(Request.Url.AbsoluteUri + "?Apple=" + lnkApple.CommandArgument);
        }
    }
    else
    {
        var nameValues = HttpUtility.ParseQueryString(Request.QueryString.ToString());
        nameValues.Set("Apple", lnkApple.CommandArgument);
        string url = Request.Url.AbsolutePath;
        string updatedQueryString = "?" + nameValues.ToString();
        Response.Redirect(url + updatedQueryString);
    }
}
protected void BananaClick(object sender, EventArgs e)
{
    LinkButton lnkBanana = sender as LinkButton;
    if (Request.Url.AbsoluteUri.Split('&').Length < 3)
    {
        if (Request.Url.AbsoluteUri.Contains('?'))
        {
            Response.Redirect(Request.Url.AbsoluteUri + "&Banana=" + lnkBanana.CommandArgument);
        }
        else
        {
            Response.Redirect(Request.Url.AbsoluteUri + "?Banana=" + lnkBanana.CommandArgument);
        }
    }

    else
    {
        var nameValues = HttpUtility.ParseQueryString(Request.QueryString.ToString());
        nameValues.Set("Banana", lnkBanana.CommandArgument);
        string url = Request.Url.AbsolutePath;
        string updatedQueryString = "?" + nameValues.ToString();
        Response.Redirect(url + updatedQueryString);
    }
}
protected void MangoClick(object sender, EventArgs e)
{
    LinkButton lnkMango = sender as LinkButton;
    if (Request.Url.AbsoluteUri.Split('&').Length < 3)
    {

        if (Request.Url.AbsoluteUri.Contains('?'))
        {
            Response.Redirect(Request.Url.AbsoluteUri + "&Mango=" + lnkMango.CommandArgument);
        }
        else
        {
            Response.Redirect(Request.Url.AbsoluteUri + "?Mango=" + lnkMango.CommandArgument);
        }
    }

    else
    {
        var nameValues = HttpUtility.ParseQueryString(Request.QueryString.ToString());
        nameValues.Set("Mango", lnkMango.CommandArgument);
        string url = Request.Url.AbsolutePath;
        string updatedQueryString = "?" + nameValues.ToString();
        Response.Redirect(url + updatedQueryString);
    }
}