require.js添加css文件实现代码：css.min.js

define(
function () {
if (typeof window == "undefined")return {
load: function (n, r, load) {
load()
}
};
var head = document.getElementsByTagName("head")[0];
var engine = window.navigator.userAgent.match(/Trident\/([^ ;]*)|AppleWebKit\/([^ ;]*)|Opera\/([^ ;]*)|rv\:([^ ;]*)(.*?)Gecko\/([^ ;]*)|MSIE\s([^ ;]*)/) || 0;
var useImportLoad = false;
var useOnload = true;
if (engine[1] || engine[7])useImportLoad = parseInt(engine[1]) < 6 || parseInt(engine[7]) <= 9; else if (engine[2])useOnload = false; else if (engine[4])useImportLoad = parseInt(engine[4]) < 18;
var cssAPI = {};
cssAPI.pluginBuilder = "./css-builder";
var curStyle;
var createStyle = function () {
curStyle = document.createElement("style");
head.appendChild(curStyle)
};
var importLoad = function (url, callback) {
createStyle();
var curSheet = curStyle.styleSheet || curStyle.sheet;
if (curSheet && curSheet.addImport) {
curSheet.addImport(url);
curStyle.onload = callback
} else {
curStyle.textContent = '@import "' + url + '";';
var loadInterval = setInterval(function () {
try {
curStyle.sheet.cssRules;
clearInterval(loadInterval);
callback()
} catch (e) {
}
}, 10)
}
};
var linkLoad = function (url, callback) {
var link = document.createElement("link");
link.type = "text/css";
link.rel = "stylesheet";
if (useOnload)link.onload = function () {
link.onload = function () {
};
setTimeout(callback, 7)
}; else var loadInterval = setInterval(function () {
for (var i = 0; i < document.styleSheets.length; i++) {
var sheet = document.styleSheets[i];
if (sheet.href == link.href) {
clearInterval(loadInterval);
return callback()
}
}
}, 10);
link.href = url;
head.appendChild(link)
};
cssAPI.normalize = function (name, normalize) {
if (name.substr(name.length - 4, 4) == ".css")name = name.substr(0, name.length - 4);
return normalize(name)
};
cssAPI.load = function (cssId, req, load, config) {
(useImportLoad ? importLoad : linkLoad)(req.toUrl(cssId + ".css"), load)
};
return cssAPI
}
);