jquery – 检查iOS版本是否> = 4.2并根据结果修改CSS

演示：http://jsfiddle.net/ThinkingStiff/LJrEW/

脚本：

var style = '';

if( getOsVersion() >= 4.2 ) {
    style = '<link rel="stylesheet" href="styles/ios.css" />';
} else {
    style = '<link rel="stylesheet" href="styles/ios_old.css" />';
};

document.head.insertAdjacentHTML( 'beforeEnd',style );

function getOsVersion() {
    var agent = window.navigator.userAgent,start = agent.indexOf( 'OS ' );

    if ( /iphone|ipod|ipad/.test( agent ) && start > -1 ) {
        return window.number( agent.substr( start + 3,3 ).replace( '_','.' ) );
    } else {
        return 0;
    };

};