在 VF 页面中导出 Excel - 使用动态图像 URL 时图像未显示

Question

I am exporting a VF page as Excel document. While I export excel file, Image cell contains blank data. Below is my VF page code. It is working fine if I am using static url ( <img alt="Image" src="https://myorgurl/resource/DefaultProfileImage" /> ) instead of dynamic Image url.

<apex:page controller="Users_Profile" contentType="application/vnd.ms-excel#Users.xls">
<table border="0" cellspacing="0" cellpadding="0" style="width:100%;">
    <thead>
        <tr>
            <th>Profile Image</th>
            <th>Name</th>
            <th>City</th>
            <th>State</th>
        </tr>
    </thead>
    <tbody>
        <apex:repeat value="{!lstUsers}" var="user">
            <tr>
                <td>
                    <image alt="Image" src="{!BaseUrl}{!URLFOR($Resource.DefaultProfileImage)}" />
                </td>
                <td>{!user.Name}</td>
                <td>{!user.City__c}</td>
                <td>{!user.State__c}</td>
            </tr>
        </apex:repeat>
    </tbody>
</table>

I have tried XML structure instead of HTML tags in VF page to get this resolved but it is not working.

Answer 1

Static resources display OK only if the "browser" has successfully logged in to Salesforce. I mean think about it, there's nothing globally unique in a link like https://eu1.salesforce.com/resources/DefaultProfileImage . Excel fails to download the image. Go to your image's url in private browsing (incognito mode), it will not display OK until you log in. This is similar to email templates that use resources or VF pages generating PDFs with images.

You need to upload the image to Documents (switch to SF Classic UI), tick "externally available image" checkbox and the link that's generated will look like https://instance.content.force.com/servlet/servlet.ImageServer?id=015...&oid=00D... . This is globally unique enough, it contains your org id and document record's id.

You can also upload the image somewhere else (Heroku?), create Site in Salesforce or Community and reference it as a public url like that... Basically anything to make the image available without logging in.

Answer 2

I Agree with Eyescream's answer. In addition to it, you can create 'Externally Available Image' document and upload your image in it. Now you can access your image without login into salesforce.

Use following steps to create a document.

1. Go to Documents tab in salesforce
2. Click on 'New Document'
3. Fill Document Name and other details
4. Select checkbox 'Externally Available Image'
5. Upload Image and Click on Save button

You will get Image preview and you can use that image url outside salesforce.