在 IE9 对象元素中查看时如何 "postMessage" 从 pdf 中托管

Question

我正在尝试用 PDF 做一个小型 PoC，但运行遇到了一个问题。我正在寻找 post 发送给 PDF 的消息，并让 PDF post 发送给浏览器的消息。

DEETS：

我正在 IE9 中的 "object" 元素中查看 PDF。我正在使用 itextsharp 在服务器上预填充 pdf 模板，注入一些应用程序级别 javascript（post 消息和消息内容），然后通过 filestreamresult 将其提供给浏览器。我正在使用 Reader 10 在 IE9 中查看 PDF。

什么有效：

到目前为止，除了 PDF post向浏览器发送消息外，一切正常。我可以 post 从浏览器向 PDF 发送消息，没问题，所有字段都已根据需要预先填写。

什么不起作用：

当我尝试使用 this.hostContainer.postMessage(["something","somethingmore"]) 时，我得到一个 Acrobat Escript window，上面写着 "hostContainer is not defined"。我也尝试过使用 "event.target.hostContainer" 但我得到 "event.target is not defined"。我不知所措，任何见解都会非常有帮助。

参考链接：

Acrobat Javascript API
Whosebug How-To on this topic
Original guide I used

代码：

我的表单视图：

<object id="pdfFrame" style="width:100%;height: 100%;" data="@Url.Action("LoadForm")">No luck :(</object>

我的自定义javascript字符串方法：

private static string GetCustomJavascript(string existingJavaScript)
    {
        const string newJs = 
        "this.disclosed = true; " +
        "if (this.external && this.hostContainer) { " +
            "function onMessageFunc( stringArray ) { " +
//                    "var name = this.myDoc.getField(personal.name); " +
//                    "var login = this.myDoc.getField(personal.loginname); " +
                    "try{" +
                        "app.alert(doc.xfa);" +
                        "console.println('Doc xfa value = ' + doc.xfa);" +
//                            "event.target.hostContainer.postMessage(['hello from pdf!']);" +
//                        "this.hostContainer.postMessage(['hello from pdf!']);"+
//                        "name.value = stringArray[0]; " +
//                        "login.value = stringArray[1]; " +
                    "} catch(e){ onErrorFunc(e); } " +
                "} " +
                "function onErrorFunc( e ) { " +
                    "console.show(); " +
                    "console.println(e.toString()); " +
                "} " +
                "try {" +
                    "if(!this.hostContainer.messageHandler) { " +
                        "this.hostContainer.messageHandler = new Object(); " +
                        "this.hostContainer.messageHandler.myDoc = this; " +
                        "this.hostContainer.messageHandler.onMessage = onMessageFunc; " +
                        "this.hostContainer.messageHandler.onError = onErrorFunc; " +
                        "this.hostContainer.messageHandler.onDisclose = function(){ return true; }; " +
                    "}" +
                "} catch(e){onErrorFunc(e);}" +
            "}";
            var jsToReturn = existingJavaScript + newJs;
            return jsToReturn;
        }

我的填写表单并发送到浏览器的方法：

public MemoryStream GetFilledRequestForm(string fileDirectory, User user, FormView formView)
        {
            var pdfStream = new MemoryStream();
            var templateFilePath = GetRequestTypeTemplateFilePath(fileDirectory, _requestModule.FormTemplateFileName);
            var pdfReader = new PdfReader(templateFilePath);
//            pdfReader.RemoveUsageRights();
            var stamper = new PdfStamper(pdfReader, pdfStream);
            var formFields = GetFormFields(user, formView, pdfReader);
            foreach (var field in formFields.Where(f => f.Value != null))
            {
                stamper.AcroFields.SetField(field.Name, field.Value);
            }
            stamper.FormFlattening = false;
            var newJs =  GetCustomJavascript(stamper.Reader.JavaScript);
            stamper.AddJavaScript("newJs", newJs);
            stamper.Close();
            byte[] byteInfo = pdfStream.ToArray();
            var outputStream = new MemoryStream();
            outputStream.Write(byteInfo, 0, byteInfo.Length);
            outputStream.Position = 0;
            return outputStream;
        }

Answer 1

好的，我已经解决了，当然是在一些帮助下。我在 this stack overflow post 找到了钥匙。在分配消息处理程序之前，我需要等待对象加载。此外，我需要 pdf javascript 中的全局变量才能 post 消息。

Html/Javascript:(这里的关键是loadListener()函数)

    @model WebModel.FormView
<object id="pdfFrame" style="width:100%;height: 100%;" data="@Url.Action("LoadForm")">No luck :(</object>
    <input id="buttonPost" type="button" value="post to pdf"/>
    <script type="text/javascript">
        var PDFObject = document.getElementById("pdfFrame");
        function loadListener() {
            if (typeof PDFObject.readyState === 'undefined') { // ready state only works for IE, which is good because we only need to do this for IE because IE sucks in the first place
                debugger;
                PDFObject.messageHandler = { onMessage: messageFunc };
                return;
            }
            if (PDFObject.readyState == 4) {
                debugger;
                PDFObject.messageHandler = { onMessage: messageFunc };
            } else {
                setTimeout(loadListener, 500);
            }
        }
        function messageFunc(data) {
            debugger;
            var messagedata = data;
            alert('finally!!');
        }

        function sendToPdf() {
            if(PDFObject!= null){
                PDFObject.postMessage(
                ["a", "b"]);
            }
        }

        $('#pdfFrame').ready(function() {
            loadListener();
            $('#buttonPost').on('click', function() {
                sendToPdf();
            });
        });

    </script>

我创建 javascript 的新函数：（这里的关键是 var appHostContainer）

private static string GetCustomJavascript(string existingJavaScript)
        {
            const string newJs = 
            "this.disclosed = true; " +
            "var appHostContainer = this.hostContainer;" + 
            "if (this.external && this.hostContainer) { " +
                "function onMessageFunc( stringArray ) { " +
//                    "var name = this.myDoc.getField(personal.name); " +
//                    "var login = this.myDoc.getField(personal.loginname); " +
                    "try{" +
                        "app.alert(stringArray);" +
                        "appHostContainer.postMessage(['hello from pdf!']);" +
//                        "name.value = stringArray[0]; " +
//                        "login.value = stringArray[1]; " +
                    "} catch(e){ onErrorFunc(e); } " +
                "} " +
                "function onErrorFunc( e ) { " +
                    "console.show(); " +
                    "console.println(e.toString()); " +
                "} " +
                "try {" +
                    "if(!this.hostContainer.messageHandler) { " +
                        "this.hostContainer.messageHandler = new Object(); " +
                        "this.hostContainer.messageHandler.myDoc = this; " +
                        "this.hostContainer.messageHandler.onMessage = onMessageFunc; " +
                        "this.hostContainer.messageHandler.onError = onErrorFunc; " +
                        "this.hostContainer.messageHandler.onDisclose = function(){ return true; }; " +
                    "}" +
                "} catch(e){onErrorFunc(e);}" +
            "}";
            var jsToReturn = existingJavaScript + newJs;
            return jsToReturn;
        }

在 IE9 对象元素中查看时如何 "postMessage" 从 pdf 中托管

How to "postMessage" to host from within pdf when viewed in IE9 object element

javascript

pdf

asp.net-mvc

itextsharp

internet-explorer-9