将按钮从C＃发送到客户端

Question

I have a helper created as follows:-

public static MvcHtmlString FileDomElement(this HtmlHelper helper, FileUpload fileUpload)
{
    string strOutput = string.Empty;

    if (fileUpload.MultipleFile)
    {
        if (string.IsNullOrEmpty(fileUpload.MimeType))
        {
            strOutput = "<input type=\"file\" multiple=\"multiple\" id=\"chooseFiles\" value=\"Choose File(s)\" onchange=\"ehDisplayFileNames();\" style=\"opacity: 0\" >";
        }
        else
        {
            strOutput = "<input type=\"file\" multiple=\"multiple\" id=\"chooseFiles\" value=\"Choose File(s)\" accept=\"" + fileUpload.MimeType + "\" onchange=\"ehDisplayFileNames();\" style=\"opacity: 0;\">";
        }
    }
    else
    {
        if (string.IsNullOrEmpty(fileUpload.MimeType))
        {
            strOutput = "<input type=\"file\" id=\"chooseFiles\" value=\"Choose File(s)\" onchange=\"ehDisplayFileNames();\" style=\"opacity: 0;\">";
        }
        else
        {
            strOutput = "<input type=\"file\" id=\"chooseFiles\" value=\"Choose File(s)\" accept=\"" + fileUpload.MimeType + "\" onchange=\"ehDisplayFileNames();\" style=\"opacity: 0;\">";
        }
    }

    return MvcHtmlString.Create(strOutput);
}

Now in the onchange event of the file I want to send the button to the backend. Because I have multiple file input elements on a single page. So I want to detect which one was clicked.

Please help me with this.

Thanks Abhishek

Answer 1

You could try catching the event info and using that to get a reference to the sender:

function ehDisplayFileNames(event) {
    console.log(event.target.id + ' has fired the event!');
}

Your markup would need to send the event: onchange="ehDisplayFileNames(event);"

Mark's comment above is very true, once you have a client side id you will still need some type of Ajax call to get this info back to the server.