Question

我是ASP.net的新手并且在显示图片时遇到了一些问题。我的设计师代码如下所示。

<div id="directory-logo-wrapper" class="floatright">
    <table id="wrapper1" runat="server">
        <tr>
            <td>
                <img src="../images/companylogo.png" alt="LogoWrapper" />
                <%--<asp:Image ID="Image1" runat="server" Visible="true" alt="LogoWrapper" />--%>
            </td>
        </tr>
    </table>
</div>

代码背后的代码如下所示。

protected void ShowImageFile(object sender, EventArgs e)
{
    byte[] bytes = {};
    bytes = (byte[])GetData("SELECT UploadedLogo FROM Projects WHERE ProjectId =" +  id).Rows[0]["UploadedLogo"];
    string base64String = Convert.ToBase64String(bytes, 0, bytes.Length);
    //Image1.ImageUrl = "data:image/png;image/jpg;base64," + base64String;
}

private DataTable GetData(string query)
{
    DataTable dt = new DataTable();
    string constr = ConnectionInfo.GetConnectionString();

    using (SqlConnection con = new SqlConnection(constr))
    {
        using (SqlCommand cmd = new SqlCommand(query))
        {
            using (SqlDataAdapter sda = new SqlDataAdapter())
            {
                cmd.CommandType = CommandType.Text;
                cmd.Connection = con;
                sda.SelectCommand = cmd;
                sda.Fill(dt);
            }
        }
        return dt;
    }
}

问题：如何在代码中设置table：wrapper1 img src因为它没有在代码后面显示。我尝试使用Image1，但它也无法访问后面的代码。

请帮帮我。

谢谢，Raja

Answer 1

尝试这样

<div id="directory-logo-wrapper" class="floatright">
    <table id="wrapper1" runat="server">
        <tr>
            <td>
               <img id="myimage" runat="server" src="../images/companylogo.png" />
            </td>
        </tr>
    </table>
</div>

您可以从Code Behind

访问Src

试试这个

                    'Get byte array from image file in the database with basic query
                    SqlDataAdapter myAdapter1 = new SqlDataAdapter("Select [logo] FROM [dbo].[tblCompanyInfo]", GlobalUser.currentConnectionString);
                    DataTable dt = new DataTable();
                    myAdapter1.Fill(dt);

                    foreach (DataRow row in dt.Rows)
                    {
                        // Get the byte array from image file
                        byte[] imgBytes = (byte[])row["logo"];

                        // If you want convert to a bitmap file
                        TypeConverter tc = TypeDescriptor.GetConverter(typeof(Bitmap));
                        Bitmap MyBitmap = (Bitmap)tc.ConvertFrom(imgBytes );


                        string imgString = Convert.ToBase64String(imgBytes);
                        // Set the source with data:image/bmp
                        myimage.Src = String.Format("data:image/Bmp;base64,{0}\"", imgString);

                    }

修改

访问GridView中的图像

private string m_ConcatUrl; protected void gridView_RowDataBound(Object sender, GridViewRowEventArgs args) { if(args.Row.RowType == DataControlRowType.DataRow) { Image imgCtrl = (Image) args.Row.FindControl("imgCtrl"); imgCtrl.ImageUrl = m_ConcatUrl; } }

<强>（或）

私有字符串m_ConcatUrl;

protected void gridView_RowDataBound(Object sender, GridViewRowEventArgs args) { if(args.Row.RowType == DataControlRowType.DataRow) { HtmlImage img = (HtmlImage) args.Row.FindControl("imgCtrl"); imgCtrl.Src= m_ConcatUrl; } }

Answer 2

您可以尝试以下方式：

HTML：

     <div id="directory-logo-wrapper" class="floatright">
        <table id="wrapper1" runat="server">
            <tr>
                <td>
                    <img src='<%# ImageUrl(ProjectId) %>' alt="LogoWrapper" />
                    <%--<asp:Image ID="Image1" runat="server" Visible="true" alt="LogoWrapper" />--%>
                </td>
            </tr>
        </table>
    </div>

代码背后：

private string ImageUrl(int ProjectId)
    {
    byte[] bytes = {};
        bytes = (byte[])GetData("SELECT UploadedLogo FROM Projects WHERE ProjectId =" +  ProjectId).Rows[0]["UploadedLogo"];
        string base64String = Convert.ToBase64String(bytes, 0, bytes.Length);
    return "data:image/png;image/jpg;base64," + base64String;
        //Image1.ImageUrl = "data:image/png;image/jpg;base64," + base64String;
    }

private DataTable GetData(string query)
{
    DataTable dt = new DataTable();
    string constr = ConnectionInfo.GetConnectionString();

using (SqlConnection con = new SqlConnection(constr))
{
    using (SqlCommand cmd = new SqlCommand(query))
    {
        using (SqlDataAdapter sda = new SqlDataAdapter())
        {
            cmd.CommandType = CommandType.Text;
            cmd.Connection = con;
            sda.SelectCommand = cmd;
            sda.Fill(dt);
        }
    }
    return dt;
}
}

希望这有帮助。

从数据库ASP.Net显示图像

2 个答案: