RE: get image side via client side script before file uplaod

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From: Steven Cheng[MSFT] (v-schang_at_online.microsoft.com)
Date: 07/16/04 

Date: Fri, 16 Jul 2004 04:50:32 GMT

Hi Moondaddy,

AS for image 's "fileSize" return -1 problem, I suspect that whether it is
caused by the image object is not completely loaded. Based on my research
,the image object contains a member property called "complete" which
indicate whether the image has been completely loaded or not. So I think we
can put a "If..." statement before we get the image's fileSize for example

if(im.complete== true)
{
   alert(im.fileSize);
}

And here is a test page I've made and you can also have a test on your side
to see whether it works.
=================aspx page====================
<HTML>
        <HEAD>
                <title>CheckImageSize</title>
                <meta name="GENERATOR" Content="Microsoft Visual Studio .NET 7.1">
                <meta name="CODE_LANGUAGE" Content="C#">
                <meta name="vs_defaultClientScript" content="JavaScript">
                <meta name="vs_targetSchema"
content="http://schemas.microsoft.com/intellisense/ie5">
                <script language="javascript">
                var im;
                function loadImage()
                {
                        im = new Image();
                        im.src = document.getElementById("imgUploader").value;
                }
                
                function checkSize()
                {
                        if(im!=null && im.complete == true)
                        {
                                alert(im.fileSize);
                        }
                        else
                        {
                                alert("not completely loaded!");
                        }
                }
                </script>
        </HEAD>
        <body>
                <form id="Form1" method="post" runat="server">
                        <table width="100%" align="center">
                                <tr>
                                        <td>
                                        <INPUT id="imgUploader" type="file" onpropertychange="loadImage()">
                                        </td>
                                </tr>
                                <tr>
                                        <td></td>
                                </tr>
                                <tr>
                                        <td>
                                        <INPUT type="button" value="Check Image File Size"
onclick="checkSize()">
                                        </td>
                                </tr>
                        </table>
                </form>
        </body>
</HTML>
=========================

Thanks.

Regards,

Steven Cheng
Microsoft Online Support

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