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C# 无法在GridView中显示图像_C#_Asp.net_Webforms - Fatal编程技术网

C# 无法在GridView中显示图像

C# 无法在GridView中显示图像,c#,asp.net,webforms,C#,Asp.net,Webforms,我无法在gridview中显示数据库中的图像。我能救他们。当我试图检索时,它没有显示任何东西,只显示一个产品名称 这是我的GridView <Columns> <asp:CommandField ShowDeleteButton="True" /> <asp:BoundField DataField="ProductName" HeaderText="ProductName" SortExpression="ProductName"

我无法在gridview中显示数据库中的图像。我能救他们。当我试图检索时,它没有显示任何东西,只显示一个产品名称

这是我的GridView

<Columns>
        <asp:CommandField ShowDeleteButton="True" />
        <asp:BoundField DataField="ProductName" HeaderText="ProductName" SortExpression="ProductName" />
         <asp:ImageField DataImageUrlField = "ProductImagesID"
            DataImageUrlFormatString = "../ImageHandler.ashx?ProductImagesID={0}"
            ControlStyle-Width = "75" ControlStyle-Height = "75"
            HeaderText = "Preview Image">
                <ControlStyle Height="100px" Width="100px"></ControlStyle>
            </asp:ImageField>
    </Columns>
ProductImageBL GetImage方法:

public static Byte[] GetImage(int productImageId)
    {
        SqlCommand cmd = new SqlCommand();
        cmd.CommandText = "Select ProductImage from ProductImages where ProductImageId = @ProductImageId";

        cmd.Parameters.AddWithValue("@ProductImageId", SqlDbType.Int).Value = productImageId;

        SqlDataReader dataReader = DbUtility.GetDataReader(cmd);
        if (dataReader.HasRows)
        {
            dataReader.Read();
            return (Byte[])dataReader[0];
        }
        else
        {
            return null;
        }
    }
请帮我翻译一下这个代码


提前感谢。

创建一个用于图像目的的页面,例如
GetMeImage.aspx
,其功能如下所示

protected void Page_Load(object sender, EventArgs e)
{
    if (Request.QueryString["ProductImagesID"] != null)
    {
string query = "Select ProductImage from ProductImages where ProductImageId = @ProductImageId";
SqlCommand cmd = new SqlCommand(query,YourConnectionObject);

    cmd.Parameters.AddWithValue("@ProductImageId", SqlDbType.Int).Value = Convert.ToInt32(Request.QueryString["ProductImagesID"]);

    SqlDataAdapter adapter = new SqlDataAdapter(cmd);
    DataTable dt = new DataTable();

    if (dt != null)
    {
        Byte[] bytes = (Byte[])dt.Rows[0]["Data"];
        Response.Buffer = true;
        Response.Charset = "";
        Response.Cache.SetCacheability(HttpCacheability.NoCache);
        Response.ContentType = dt.Rows[0]["ContentType"].ToString();
        Response.AddHeader("content-disposition", "attachment;filename="
        + dt.Rows[0]["Name"].ToString());
        Response.BinaryWrite(bytes);
        Response.Flush();
        Response.End();
    }
}
}
在gridview中添加模板字段

<asp:ImageField DataImageUrlField = "ProductImagesID"
            DataImageUrlFormatString = "../GetMeImage.aspx?ProductImagesID={0}"
            ControlStyle-Width = "75" ControlStyle-Height = "75"
            HeaderText = "Preview Image">
                <ControlStyle Height="100px" Width="100px"></ControlStyle>
            </asp:ImageField>

请编辑您的问题以包含代码的相关部分。这个社区不喜欢代码的外部链接,如果您直接提供代码,您的问题很可能会得到答案。
<asp:ImageField DataImageUrlField = "ProductImagesID"
            DataImageUrlFormatString = "../GetMeImage.aspx?ProductImagesID={0}"
            ControlStyle-Width = "75" ControlStyle-Height = "75"
            HeaderText = "Preview Image">
                <ControlStyle Height="100px" Width="100px"></ControlStyle>
            </asp:ImageField>