如何知道浏览器是否有PDF查看器？

Question

我在iframe中查看PDF.它工作正常.但是一些客户端无法在IE中看到它.他们将其作为下载选项.

如何确定浏览器是否具有pdf查看器并提示用户他没有pdf查看器？

注意:我使用的是asp.net mvc 5(c#).

我试过这个,但是没有帮助我.我的一些客户端的问题有Adobe PDF,因此下面的答案没有问题.但那些有nitropdf或chrome pdf查看器的人,下面的回答并没有帮助我.我想识别所有pdf查看器.否则如果客户端有某种pdf查看器,那么还会显示没有安装pdf查看器的警报.那是错的.

我通过获得عبدالنورالتومي的答案来应用此代码,它适用于chrome和mozilla.这是我修改过的js.

但IE仍然没有回应它.我不知道如何在IE中检查它是否有pdf查看器.对于IE,虽然有pdf查看器,但我得到了以下错误:

Answer 1

有一个JS解决方案:

var hasPdfViewer = getAcrobatInfo().acrobat ==="installed";

已知API getAcrobatInfo是:

// http://thecodeabode.blogspot.com
// @author: Ben Kitzelman
// @license:  FreeBSD: (http://opensource.org/licenses/BSD-2-Clause) Do whatever you like with it
// @updated: 03-03-2013

var getAcrobatInfo = function() {

  var getBrowserName = function() {
    return this.name = this.name || function() {
      var userAgent = navigator ? navigator.userAgent.toLowerCase() : "other";

      if(userAgent.indexOf("chrome") > -1)        return "chrome";
      else if(userAgent.indexOf("safari") > -1)   return "safari";
      else if(userAgent.indexOf("msie") > -1)     return "ie";
      else if(userAgent.indexOf("firefox") > -1)  return "firefox";
      return userAgent;
    }();
  };

  var getActiveXObject = function(name) {
    try { return new ActiveXObject(name); } catch(e) {}
  };

  var getNavigatorPlugin = function(name) {
    for(key in navigator.plugins) {
      var plugin = navigator.plugins[key];
      if(plugin.name == name) return plugin;
    }
  };

  var getPDFPlugin = function() {
    return this.plugin = this.plugin || function() {
      if(getBrowserName() == 'ie') {
        //
        // load the activeX control
        // AcroPDF.PDF is used by version 7 and later
        // PDF.PdfCtrl is used by version 6 and earlier
        return getActiveXObject('AcroPDF.PDF') || getActiveXObject('PDF.PdfCtrl');
      }
      else {
        return getNavigatorPlugin('Adobe Acrobat') || getNavigatorPlugin('Chrome PDF Viewer') || getNavigatorPlugin('WebKit built-in PDF');
      }
    }();
  };

  var isAcrobatInstalled = function() {
    return !!getPDFPlugin();
  };
  var getAcrobatVersion = function() {
    try {
      var plugin = getPDFPlugin();

      if(getBrowserName() == 'ie') {
        var versions = plugin.GetVersions().split(',');
        var latest   = versions[0].split('=');
        return parseFloat(latest[1]);
      }
      if(plugin.version) return parseInt(plugin.version);
      return plugin.name
    }
    catch(e) {
      return null;
    }
  }

  // The returned object
  return {
    browser:        getBrowserName(),
    acrobat:        isAcrobatInstalled() ? 'installed' : false,
    acrobatVersion: getAcrobatVersion()
  };
};

Answer 2

作为替代方案，您可以使用像viewer.js 这样的库在容器中显示您的pdf。

请参阅http://viewerjs.org/

Answer 3

我通过عبدالنورالتومي的帮助尝试了以下解决方案,这有助于chrome和mozilla中的任何pdf查看器

    var getAcrobatInfo = function () {

        var getBrowserName = function () {
            return this.name = this.name || function () {
                var userAgent = navigator ? navigator.userAgent.toLowerCase() : "other";

                if (userAgent.indexOf("chrome") > -1) { return "chrome"; }
                else if (userAgent.indexOf("safari") > -1) { return "safari"; }
                else if (userAgent.indexOf("msie") > -1 || userAgent.indexOf("trident") > -1) { return "ie"; }
                else if (userAgent.indexOf("firefox") > -1) { return "firefox";}
                return userAgent;
            }();
        };

        var getActiveXObject = function (name) {
            try { return new ActiveXObject(name); } catch (e) { }
        };

        var getNavigatorPlugin = function (name) {
            try {
                for (key in navigator.plugins) {
                    var plugin = navigator.plugins[key];
                    if (plugin.name.toLowerCase().indexOf(name) > -1) { return plugin; }
                }
            } catch (e) {

            }

        };

        var getPDFPlugin = function () {
            return this.plugin = this.plugin || function () {
                if (getBrowserName() == 'ie') {
                    return getActiveXObject('AcroPDF.PDF') || getActiveXObject('PDF.PdfCtrl');
                }
                else {
                    return getNavigatorPlugin('adobe acrobat') || getNavigatorPlugin('pdf') || getNavigatorPlugin('foxit reader');  // works for all plugins which has word like 'adobe acrobat', 'pdf' and 'foxit reader'.
                }
            }();
        };

        var isAcrobatInstalled = function () {
            return !!getPDFPlugin();
        };

        var getAcrobatVersion = function () {
            try {
                var plugin = getPDFPlugin();

                if (getBrowserName() == 'ie') {
                    var versions = plugin.GetVersions().split(',');
                    var latest = versions[0].split('=');
                    return parseFloat(latest[1]);
                }

                if (plugin.version) return parseInt(plugin.version);
                return plugin.name

            }
            catch (e) {
                return null;
            }
        };

        return {
            browser: getBrowserName(),      // Return browser name
            acrobat: isAcrobatInstalled() ? true : false,   // return pdf viewer is enabled or not
            acrobatVersion: getAcrobatVersion()  // reurn acrobat version for browser


   };
}

我有IE的跟随错误,虽然我在我的浏览器中安装了pdf viewer:

然后我通过这个链接解决了它.

然后我为IE 11添加新条件trident,现在它工作正常.我还添加了检查选项foxit reader.您还可以在条件中添加另一个pdf阅读器名称.

Answer 4

我认为可以从导航器 MimeType 中检查

function isSupportPDF() {
    var hasPDFViewer = false;
    try {
        var pdf =
            navigator.mimeTypes &&
            navigator.mimeTypes["application/pdf"]
                ? navigator.mimeTypes["application/pdf"].enabledPlugin
                : 0;
        if (pdf) hasPDFViewer = true;
    } catch (e) {
        if (navigator.mimeTypes["application/pdf"] != undefined)
            hasPDFViewer = true;
    }

    return hasPDFViewer;
}