How to Consume Web API Using Web Request

This article explains how to consume a Web API using a Web Request and deserialize it in JSON and bind data in a grid view.

Getting Started

Create a new project in Visual Studio 2012 and select "Empty ASP.NET Web Application" and click "OK".

First of all, add two classes:

public class wrapper
{
    public List<SalesPerson> salesperson { get; set; }
}
public class SalesPerson
{
    public String Code { get; set; }
    public String databaseID { get; set; }
    public String name { get; set; }
    public String path { get; set; }
    public String definition { get; set; }
}

Now add your web api URL:

string _URL = "https://api.icarol.com/v1/Resource/Taxonomy?db=2285";

Now drag and drop a GridView data control onto the page.

Now add these namespaces:

using System.IO;
using System.Web.Script.Serialization;
protected void Page_Load(object sender, EventArgs e)
{
    WebRequest req = WebRequest.Create(_URL);
    req.Method = "GET";
    req.Headers.Add("key");
    req.ContentType = "application/json; charset=utf-8";
    WebResponse resp = req.GetResponse();
    Stream stream = resp.GetResponseStream();
    StreamReader re = new StreamReader(stream);
    String json = re.ReadToEnd();
    json = "{\"SalesPerson\":" + json + "}";
    wrapper w = (wrapper)new JavaScriptSerializer().Deserialize(json, typeof(wrapper));
    GridView1.DataSource = w.salesperson;
    GridView1.DataBind();
}

GridView

<asp:GridView ID="GridView1" runat="server" Width="500px" CellPadding="4" ForeColor="#333333" GridLines="None" EmptyDataText="Data Not Found">
    <AlternatingRowStyle BackColor="White" />
    <EditRowStyle BackColor="#7C6F57" />
    <FooterStyle BackColor="#1C5E55" Font-Bold="True" ForeColor="White" />
    <HeaderStyle BackColor="#1C5E55" Font-Bold="True" ForeColor="White" />
    <PagerStyle BackColor="#666666" ForeColor="White" HorizontalAlign="Center" />
    <RowStyle BackColor="#E3EAEB" />
    <SelectedRowStyle BackColor="#C5BBAF" Font-Bold="True" ForeColor="#333333" />
    <SortedAscendingCellStyle BackColor="#F8FAFA" />
    <SortedAscendingHeaderStyle BackColor="#246B61" />
    <SortedDescendingCellStyle BackColor="#D4DFE1" />
    <SortedDescendingHeaderStyle BackColor="#15524A" />
</asp:GridView>

Now run the application to see the output.



Image 1.