js 检测 是否安装abode

<script language="javascript" type="text/javascript">
Check_AdobeReader();
function Check_AdobeReader() {
var displayString;
var acrobat = new Object();
acrobat.installed = false;
acrobat.version = "0.0";

if (navigator.plugins && navigator.plugins.length) {
for (x = 0; x < navigator.plugins.length; x++) {
if (navigator.plugins[x].description.indexOf("Adobe Acrobat") != -1) {
acrobat.version = parseFloat(navigator.plugins[x].description.split("Version ")[1]);
if (acrobat.version.toString().length == 1) acrobat.version += ".0";
acrobat.installed = true;
displayString = "Acrobat Version: " + acrobat.version;
break;
} else if (navigator.plugins[x].description.indexOf("Adobe PDF Plug-In") != -1) {
acrobat.installed = true;
acrobat.version = "8+";
displayString = "Acrobat Version 8 or Above";
}
}
} else if (window.ActiveXObject) {
for (x = 2; x < 10; x++) {
try {
oAcro = eval("new ActiveXObject('PDF.PdfCtrl." + x + "');");
if (oAcro) {
acrobat.installed = true;

acrobat.version = x + ".0";
displayString = "Acrobat Version: " + acrobat.version;
}
}
catch (e) { }
}

try {
oAcro4 = new ActiveXObject("PDF.PdfCtrl.1");
if (oAcro4) {
acrobat.installed = true;
acrobat.version = '4.0';
displayString = 'Acrobat Version: ' + acrobat.version;
}
}
catch (e) { }

try {
oAcro7 = new ActiveXObject('AcroPDF.PDF.1');
if (oAcro7) {
acrobat.installed = true;
acrobat.version = '7.0';
displayString = 'Acrobat Version: ' + acrobat.version;
}
}
catch (e) { }
}

alert(acrobat.installed + displayString);
if( acrobat.installed == false){
alert(" 你需要先安装Adobe Reader才能正常浏览文件.");
}else{

}

}

</script>