Question

我有一个名为PIMAGE的字段表我无法显示此字段。 gridview命名为：dgw- 我的问题是gridview不显示图像我的代码：

   protected void Page_Load(object sender, EventArgs e)
    {
        StorDataContext stor = new StorDataContext();

        var res = (from r in stor.Products
                   where r.PID!=13
                   select new {
                       name=r.PName,date=System.DateTime.Now.ToString(),company=r.Company,price=r.Price,quantity=r.Quantity,color=r.Color,size=r.Size,weight=r.PWeight,
                       PImage = r.PID});

        GridView1.Visible = true;
        GridView1.DataSource = res.ToList();
        GridView1.DataBind();
    }

并且可能是ashx

public class ShowImg : IHttpHandler {

    public void ProcessRequest(HttpContext context)
    {
        Int32 pid;
        if (context.Request.QueryString["getID"] != null)
        {
            pid = Convert.ToInt32(context.Request.QueryString["getID"]);
            context.Response.ContentType = "image/jpeg";
            Stream strm = GetImage(pid);
            byte[] buffer = new byte[4096];
            int byteSeq = strm.Read(buffer, 0, 4096);
            while (byteSeq > 0)
            {
                context.Response.OutputStream.Write(buffer, 0, byteSeq);
                byteSeq = strm.Read(buffer, 0, 4096);
            }
        }
    }
        public Stream GetImage(int pid)
    {

        StorDataContext stor = new StorDataContext();    
        System.Data.Linq.Binary b = null;
        byte[] ibyte = null;


        Product product1 = stor.Products.First(p => p.PID == pid);

        b = product1.PImage;
        ibyte = b.ToArray();

        return new MemoryStream((byte[])ibyte);
    }

和aspx

<asp:TemplateField HeaderText="PImage">

                    <ItemTemplate>
                        <asp:Image ID="Image1" runat="server" ImageUrl='<%# "~/ShowImg.ashx?id=" + Eval("PImage")  %>' />
                    </ItemTemplate>

                </asp:TemplateField>

怎么了？使用asp.net - sql server - linq

Answer 1

我假设您的意思是您在数据库中有一个图像字段。网上有很多可用的例子，这里有asp.net forums

的例子。

短版本是，您可以设置控件   在gridview中显示图像。在ImageField上，你   将使用DataImageUrlField属性来引用该名称   数据库中包含二进制图像数据的字段。也在   ImageField，使用DataImageUrlFormatString来定义路径   例如，指向ASPX处理程序页面并传递给它   DataImageUrlField中的特定ID值。

相关的代码行可能如下所示：

＆lt; asp：ImageField DataImageUrlField =＆＃34; MyImageID＆＃34;   DataImageUrlFormatString =＆＃34; MyHandlerPage.aspx theImageID = {0}＆＃34？; /＆GT;一个   完整的示例，使用此方法并显示代码   处理程序页面位于：

http://www.highoncoding.com/Articles/207_Displaying_Images_from_Database_in_GridView.aspx

或查看this one

public void ProcessRequest (HttpContext context) {
    string connectionString = ConfigurationManager.ConnectionStrings["DBConnection"].ConnectionString;
    SqlConnection conn = new SqlConnection(connectionString);
    SqlCommand cmd = new SqlCommand();
    cmd.CommandText = "Select [Content] from Images where ID =@ID";
    cmd.CommandType = CommandType.Text;
    cmd.Connection = conn;

    SqlParameter ImageID = new SqlParameter("@ID", SqlDbType.BigInt);
    ImageID.Value = context.Request.QueryString["ID"];
    cmd.Parameters.Add(ImageID);
    conn.Open();
    SqlDataReader dReader = cmd.ExecuteReader();
    dReader.Read();
    context.Response.BinaryWrite((byte[])dReader["Content"]);
    dReader.Close();
    conn.Close();
}

和aspx代码

<asp:GridView ID="GVImages" runat="server" AutoGenerateColumns="false" HeaderStyle-BackColor="CornflowerBlue" HeaderStyle-Font-Bold="true" HeaderStyle-ForeColor="White" CellPadding="5">
        <Columns>

        <asp:BoundField DataField="Name" HeaderText="Description" />
        <asp:BoundField DataField="Type" HeaderText="Type" />

        <asp:TemplateField HeaderText="Image">
        <ItemTemplate>
        <asp:Image ID="Image1" runat="server" Width="200px" Height="200px" 
                   ImageUrl='<%# "ImageHandler.ashx?ID=" + Eval("ID")%>'/>
        </ItemTemplate>
        </asp:TemplateField>

        </Columns>        
        </asp:GridView>

和你在aspx.cs中的page_load

protected void Page_Load(object sender, EventArgs e)
{
    if (!IsPostBack)
    {
        string connectionString = ConfigurationManager.ConnectionStrings["DBConnection"].ConnectionString;
        DataTable dt = new DataTable();
        SqlConnection conn = new SqlConnection(connectionString);
        using (conn)
        {
            SqlDataAdapter ad = new SqlDataAdapter("SELECT * FROM Images", conn);
            ad.Fill(dt);
        }
        GVImages.DataSource = dt;
        GVImages.DataBind();
    }
}

最后是你的web.config

<configuration>
  <connectionStrings>
    <add name="DBConnection" connectionString="Data Source=.\SQLEXPRESS;Initial Catalog=TESTDB;Trusted_Connection=yes;" providerName="System.Data.SqlClient"/>
    <!--<add name="BONConnection" connectionString="Data Source=XXX.com;Initial Catalog=DBNAME;User Id=UserName;Password=YourPassword;" providerName="System.Data.SqlClient" />-->
  </connectionStrings>
...................
...................

如何在GridView表单数据库linq中显示图像

1 个答案: