在gridview中显示数据表中的图像

Question

我在我的 asp 页面的 on-load() 函数上绑定了数据，我可以检索所有数据，但很遗憾我看不到图像。我附上了代码，请给我一些想法，我该怎么做？帮助我在网格视图中显示图像。

<asp:GridView ID="GridView2" runat="server">

             <AlternatingRowStyle BackColor="#CCCCCC" />
             <HeaderStyle BackColor="#C19E45" ForeColor="White" />
             <SelectedRowStyle BackColor="#3333CC" ForeColor="Red" />
</asp:GridView>


 protected void Page_Load(object sender, EventArgs e)
{
    DataTable dt = client.viewClients();
    DataTable  newdt = new DataTable();//for filtering data
     newdt.Columns.Add("id", typeof(string));
     newdt.Columns.Add("Name", typeof(string));
     newdt.Columns.Add("Father/Husband", typeof(string));
     newdt.Columns.Add("Cnic", typeof(string));
     newdt.Columns.Add("Occupation", typeof(string));
     newdt.Columns.Add("Present_Address", typeof(string));
     newdt.Columns.Add("Telephone", typeof(string));
     newdt.Columns.Add("Phone", typeof(string));
     newdt.Columns.Add("Email", typeof(string));
     newdt.Columns.Add("Permanent_address", typeof(string));
     newdt.Columns.Add("Nominee_name", typeof(string));
     newdt.Columns.Add("Nominee_address", typeof(string));
     newdt.Columns.Add("Nominee_cnic", typeof(string));
     newdt.Columns.Add("nominee_no", typeof(string));
     newdt.Columns.Add("Image", typeof(string));
     newdt.Columns.Add("registeration_no", typeof(string));


    foreach (DataRow row in dt.Rows)
    {
        DataRow nrow = newdt.NewRow();  //creating newRow
       // byte[] imgarray = (byte[])row["image"];
       // System.Drawing.Image img = client.byteArrayToImage(imgarray);
        nrow["id"]=row["id"];
        nrow["Name"] = row["name"];
        nrow["Father/Husband"] = row["relation_of"];
        nrow["Cnic"] = row["applicant_cnic"];
        nrow["Occupation"] = row["occupation"];
        nrow["Present_Address"] = row["present_address"];
        nrow["Telephone"] = row["telephone"];
        nrow["Phone"] = row["mobile"];
        nrow["Email"] = row["email"];
        nrow["Permanent_address"] = row["permanent_address"];
        nrow["Nominee_name"] = row["nominee_name"];
        nrow["Nominee_address"] = row["nominee_address"];
        nrow["Nominee_cnic"] = row["nominee_cnic"];
        nrow["nominee_no"] = row["nominee_no"];
        nrow["Image"] = row["image"];
        nrow["registeration_no"] = row["registeration_no"];

        newdt.Rows.Add(nrow);

    }
    GridView2.DataSource = newdt;
    GridView2.DataBind();
}

这是从代码中得到的输出

Answer 1

您将图像列创建为字符串，它不是字符串。您需要在GridView 控件中创建图像模板并将模板内的图像绑定到图像的二进制数据：

背后的代码：

protected void Page_Load(object sender, EventArgs e)
{
    this.BindData();
}

private void BindData()
{
    string connString = ConfigurationManager.ConnectionStrings["connectionString"].ConnectionString;
    var table = new DataTable();

    using(var connection = new SqlConnection(connString))
    {
        using(var command = new SqlCommand("SELECT Name,Image FROM Colour",connection))
        {
            connection.Open();

            var adapter = new SqlDataAdapter(command);
            adapter.Fill(table);

            connection.Close();
        }
    }
    GridView2.DataSource = table;
    GridView2.DataBind();
}

.ASPX：

<asp:GridView ID="GridView2" runat="server" AutoGenerateColumns="false">
    <Columns>
        <asp:BoundField DataField="Name" HeaderText="Name" />
        <asp:TemplateField>
            <HeaderTemplate>Image</HeaderTemplate>
            <ItemTemplate>
                <img src='data:image/jpg;base64,<%# Eval("Image") != System.DBNull.Value ? Convert.ToBase64String((byte[])Eval("Image")) : string.Empty %>' alt="image" height="100" width="200" />
            </ItemTemplate>
        </asp:TemplateField>
    </Columns>
</asp:GridView>

输出：

Answer 2

对此的最佳答案是 tomake handler http://codedisplay.com/display-images-in-gridview-from-sql-server-database-table-using-asp-net-c-vb-net/