微软官方的一段JavaScript判断.net环境

<HTML> 
<HEAD> 
<TITLE>Test for the .NET Framework 3.5</TITLE> 
<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=utf-8" /> 
<SCRIPT LANGUAGE="JavaScript"> 
<!-- 
var dotNETRuntimeVersion = "3.5.0.0"; 
function window::onload() 
{ 
if (HasRuntimeVersion(dotNETRuntimeVersion)) 
{ 
result.innerText = 
"This machine has the correct version of the .NET Framework 3.5." 
} 
else 
{ 
result.innerText = 
"This machine does not have the correct version of the .NET Framework 3.5." + 
" The required version is v" + dotNETRuntimeVersion + "."; 
} 
result.innerText += "\n\nThis machine's userAgent string is: " + 
navigator.userAgent + "."; 
} 
// 
// Retrieve the version from the user agent string and 
// compare with the specified version. 
// 
function HasRuntimeVersion(versionToCheck) 
{ 
var userAgentString = 
navigator.userAgent.match(/.NET CLR [0-9.]+/g); 
if (userAgentString != null) 
{ 
var i; 
for (i = 0; i < userAgentString.length; ++i) 
{ 
if (CompareVersions(GetVersion(versionToCheck), 
GetVersion(userAgentString[i])) <= 0) 
return true; 
} 
} 
return false; 
} 
// 
// Extract the numeric part of the version string. 
// 
function GetVersion(versionString) 
{ 
var numericString = 
versionString.match(/([0-9]+)\.([0-9]+)\.([0-9]+)/i); 
return numericString.slice(1); 
} 
// 
// Compare the 2 version strings by converting them to numeric format. 
// 
function CompareVersions(version1, version2) 
{ 
for (i = 0; i < version1.length; ++i) 
{ 
var number1 = new Number(version1[i]); 
var number2 = new Number(version2[i]); 
if (number1 < number2) 
return -1; 
if (number1 > number2) 
return 1; 
} 
return 0; 
} 
--> 
</SCRIPT> 
</HEAD> 
<BODY> 
<div id="result" /> 
</BODY> 
</HTML>

  

posted @ 2013-07-25 14:16  马老虎  阅读(300)  评论(0编辑  收藏  举报