如何让 ActiveX 与 IE 受保护模式配合使用？
本文讨论如何在Internet Explorer保护模式下使用Dynamic Web TWAIN ActiveX控件。
引言
本文讨论如何在Internet Explorer保护模式下使用Dynamic Web TWAIN ActiveX控件。
背景
自从Windows Vista上的Internet Explorer 7发布以来，保护模式作为一项新的安全功能被引入。它基于Windows Vista的新的访问控制安全机制。在保护模式下运行时，Internet Explorer是一个低完整性进程，并且对用户系统的访问权限有限。
虽然保护模式更好地保护系统免受Internet的侵害，但是当ActiveX需要与高完整性对象通信时，它会导致问题。
Dynamsoft的Dynamic Web TWAIN是一款用于Web应用程序的文档扫描SDK。您可以将Dynamic Web TWAIN嵌入到您的网站中，以使用户能够在线扫描文档。它包括一个ActiveX版本，该版本允许用户在IE（x86 / x64）中从TWAIN兼容的扫描仪获取图像。在Windows Vista及更高版本上运行Dynamic Web TWAIN时，默认情况下会启用IE保护模式，因此用户始终会遇到以下问题
- ActiveX无法访问连接到用户计算机的扫描仪
- 由于权限不足，当ActiveX尝试从扫描仪获取图像时，IE崩溃
一种可能的解决方案是让最终用户手动关闭保护模式，以使ActiveX控件正常工作，但这不方便并且对用户不友好。
使用保护模式
为了解决保护模式引起的问题，Dynamsoft引入了一种新方法。Dynamic Web TWAIN没有在具有较低级别访问权限的浏览器进程下运行ActiveX，而是使用独立的代理进程与扫描仪进行通信，从而获得更好的兼容性和鲁棒性。代理进程具有中等级别的权限，因此它可以访问中等完整性对象。它具有以下优点
- 避免因扫描仪驱动程序问题引起的浏览器崩溃，从而提高Web应用程序的鲁棒性。独立进程不会影响浏览器进程。
- 用于扫描的独立进程比浏览器进程具有更高的权限级别。这可以解决扫描问题，例如浏览器无法成功访问扫描仪源，这是由Windows / IE的增强的安全功能引起的。
Using the Code
您可以简单地将BrokerProcessType属性设置为1，以启用单独的代理进程进行扫描。以下是在浏览器中使用Dynamic Web TWAIN进行ADF扫描（分辨率为100并使用灰色）的简单示例。
window.onload = DW_Pageonload;
function DW_PageonloadInner() {//Detect Environment
// Get User Agent Value
ua = (navigator.userAgent.toLowerCase());
// Set the Explorer Type
if (ua.indexOf("msie") != -1)
DW_InIE = true;
else
DW_InIE = false;
// Set the Operating System Type
if (ua.indexOf("macintosh") != -1)
DW_InWindows = false;
else
DW_InWindows = true;
// Set the x86 and x64 type
if (ua.indexOf("win64") != -1 && ua.indexOf("x64") != -1)
DW_InWindowsX86 = false;
else
DW_InWindowsX86 = true;
}
function DW_CreateControl() {
var objString = "";
var DWTContainer;
// For IE, render the ActiveX Object
if (DW_InIE) {
/*Only useful in version 8.* or earlier
///////////////////////////////////////
objString = "<object classid='clsid:" + DW_PROCLASSID + "' style='display:none;'><param name='LPKPath' value='" + DW_LPKPath + "'/></object>";
///////////////////////////////////////
*/
objString += "<object id='" + DW_ObjectName + "' style='width:" + DW_Width + "px;height:" + DW_Height + "px'";
if (DW_InWindowsX86)
objString += "codebase='" + DW_CABX86Path + "#version=" + DW_VersionCode + "' ";
else
objString += "codebase='" + DW_CABX64Path + "#version=" + DW_VersionCode + "' ";
var temp = DW_IsTrial ? DW_TRAILCLASSID : DW_FULLCLASSID;
objString += " classid='clsid:" + temp + "' viewastext>";
objString += " <param name='Manufacturer' value='DynamSoft Corporation' />";
objString += " <param name='ProductFamily' value='" + DW_ProductName + "' />";
objString += " <param name='ProductName' value='" + DW_ProductName + "' />";
//objString += " <param name='wmode' value='transparent'/> ";
objString += " </object>";
}
// For non-IE, render the embed object
else {
objString = " <embed id='" + DW_ObjectName + "'style='display: inline; width:" + DW_Width + "px;height:" + DW_Height + "px' id='" + DW_ObjectName + "' type='" + DW_MIMETYPE + "'";
objString += " OnPostTransfer='Dynamsoft_OnPostTransfer' OnPostAllTransfers='Dynamsoft_OnPostAllTransfers'";
objString += " OnMouseClick='Dynamsoft_OnMouseClick' OnPostLoad='Dynamsoft_OnPostLoadfunction'";
objString += " OnImageAreaSelected = 'Dynamsoft_OnImageAreaSelected'";
objString += " OnImageAreaDeSelected = 'Dynamsoft_OnImageAreaDeselected'";
objString += " OnMouseDoubleClick = 'Dynamsoft_OnMouseDoubleClick'";
objString += " OnMouseRightClick = 'Dynamsoft_OnMouseRightClick'";
objString += " OnTopImageInTheViewChanged = 'Dynamsoft_OnTopImageInTheViewChanged'";
objString += " OnGetFilePath='Dynamsoft_OnGetFilePath'";
if (DW_InWindows)
objString += " pluginspage='" + DW_MSIPath + "'></embed>";
else
objString += " pluginspage='" + DW_PKGPath + "'></embed>";
}
DWTContainer = document.getElementById(DW_DWTContainerID);
DWTContainer.innerHTML = objString;
DWObject = document.getElementById(DW_ObjectName);
}
function DW_Pageonload() {
DW_PageonloadInner(); //Detect environment
InitInfo(); //Add guide info
DW_CreateControl(); //Create an instance of the component in the DIV assigned by DW_DWTContainerID
vShowNoControl = false; //By default, we assume the control is not loaded
//Set interval to check if the control is fully loaded.
DW_Seed = setInterval(DW_ControlDetect, 500);
}
// Check if the control is fully loaded.
function DW_ControlDetect() {
// If the ErrorCode is 0, it means everything is fine for the control. It is fully loaded.
if (DWObject.ErrorCode == 0) {
/*Only useful in version 9.0 or later*/
/////////////////////////////////////// Please put your product key below
DWObject.ProductKey = "391243D92C15C4BE5C77E6EC25D16FC6D9754433530E517A67371A97AD158D173373ABC58E8272C940F1ACE1E97C953920000000";
///////////////////////////////////////
DWObject.BrokerProcessType = 1; //scan in a separate brokerprocess
DW_Pause();
// For IE, attach events
if (DW_InIE) {
DWObject.attachEvent('OnPostTransfer', Dynamsoft_OnPostTransfer);
DWObject.attachEvent('OnPostAllTransfers', Dynamsoft_OnPostAllTransfers);
DWObject.attachEvent('OnMouseClick', Dynamsoft_OnMouseClick);
DWObject.attachEvent('OnPostLoad', Dynamsoft_OnPostLoadfunction);
DWObject.attachEvent('OnImageAreaSelected', Dynamsoft_OnImageAreaSelected);
DWObject.attachEvent('OnMouseDoubleClick', Dynamsoft_OnMouseDoubleClick);
DWObject.attachEvent('OnMouseRightClick', Dynamsoft_OnMouseRightClick);
DWObject.attachEvent('OnTopImageInTheViewChanged', Dynamsoft_OnTopImageInTheViewChanged);
DWObject.attachEvent('OnImageAreaDeSelected', Dynamsoft_OnImageAreaDeselected);
DWObject.attachEvent('OnGetFilePath', Dynamsoft_OnGetFilePath);
}
}
else {
if (vShowNoControl == false) {
DW_NoControl();
vShowNoControl = true;
}
}
DW_Timeout = setTimeout(function () { }, 10);
}
function DW_Pause() {
clearInterval(DW_Seed);
}
function DW_NoControl() {
// Display the message and hide the main control
DW_CreateNonInstallDivPlugin();
document.getElementById(DW_DWTNonInstallContainerID).style.display = "inline";
document.getElementById(DW_DWTContainerID).style.display = "none";
}
function DW_CreateNonInstallDivPlugin() {
var varHref = "";
if (DW_InIE) {
var ObjString = "<div style='display: block; border:solid black 1px; text-align:center; width:" + DW_Width + "px;height:" + DW_Height + "px'>";
ObjString += "<ul style='padding-top:100px;'>";
ObjString += "<li>The Component is not installed</li>";
ObjString += "<li>You need to download and install the ActiveX to use this sample.</li>";
ObjString += "<li>Please follow the instructions in the information bar.</li>";
ObjString += "</ul></div>";
}
else {
if (DW_InWindows) {
if (location.hostname != "")
varHref = "http://" + location.host + location.pathname.substring(0, location.pathname.lastIndexOf('/')) + "/" + DW_MSIPath;
else
varHref = DW_MSIPath;
}
else {
if (location.hostname != "")
varHref = "http://" + location.host + location.pathname.substring(0, location.pathname.lastIndexOf('/')) + "/" + DW_PKGPath;
else
varHref = DW_PKGPath;
}
var ObjString = "<div style='display: block; border:solid black 1px; text-align:center; width:" + DW_Width + "px;height:" + DW_Height + "px'>";
ObjString += "<ul style='padding-top:100px;'>";
ObjString += "<li>The Component is not installed</li>";
ObjString += "<li>You need to download and install the plug-in to use this sample.</li>";
ObjString += "<li>Please click the below link to download it.</li>";
ObjString += "<li>After the installation, please RESTART your browser.</li>";
ObjString += "<li><a href='" + varHref + "'>Download</a></li>";
ObjString += "</ul></div>";
}
document.getElementById(DW_DWTNonInstallContainerID).innerHTML = ObjString;
}
function DW_AcquireImage() {
DWObject.SelectSource(); //show the available devices
DWObject.OpenSource();
DWObject.IfShowUI = false; //hide the user interface of the TWAIN source
DWObject.PixelType = 1; //scan images in gray
DWObject.Resolution = 100; //set resolution to 100
DWObject.IfFeederEnabled = true;
DWObject.XferCount = -1;
DWObject.IfAutoFeed = true; //auto feed
DWObject.IfDisableSourceAfterAcquire = true;
DWObject.AcquireImage();
}
当您运行嵌入Dynamic Web TWAIN的Web应用程序时，您将在任务管理器中看到用于扫描的代理进程
结论
通过在Dynamic Web TWAIN 9.0中使用独立的代理进程进行扫描，大大提高了Web扫描应用程序的安全性和鲁棒性。用户会发现更容易和更顺畅地激活和使用ActiveX控件，以便在更高版本的Windows IE上进行Web扫描。
有关Dynamic Web TWAIN的更多信息，请访问Dynamsoft网站。
资源
Dynamic Web TWAIN是一个客户端Web扫描控件，您可以将其嵌入到您的Web应用程序中。它允许用户从TWAIN兼容的扫描仪扫描文档，或从数码相机获取图像。
Dynamic Web TWAIN支持Windows和Mac上的所有主流浏览器。
ActiveX版本 – 与x84 / x64 IE一起使用
插件版本 – 与Windows上的Chrome，Firefox，Safari，Opera一起使用
Mac版本 - 与Mac上的Chrome，Firefox，Safari，Opera一起使用