Question

如何使用原生JS实现类似jQuery的getJSON功能

Answer 1

var $ = {
getJSON: function(url, params, callbackFuncName, callback){
var paramsUrl ="",
jsonp = this.getQueryString(url)[callbackFuncName];
for(var key in params){
paramsUrl+="&"+key+"="+encodeURIComponent(params[key]);
}
url+=paramsUrl;
window[jsonp] = function(data) {
window[jsonp] = undefined;
try {
delete window[jsonp];
} catch(e) {}

if (head) {
head.removeChild(script);
}
callback(data);
};
var head = document.getElementsByTagName('head')[0];
var script = document.createElement('script');
script.charset = "UTF-8";
script.src = url;
head.appendChild(script);
return true;
},
getQueryString: function(url) {
var result = {}, queryString = (url && url.indexOf("?")!=-1 && url.split("?")[1]) || location.search.substring(1),
re = /([^&=]+)=([^&]*)/g, m;
while (m = re.exec(queryString)) {
result[decodeURIComponent(m[1])] = decodeURIComponent(m[2]);
}
return result;
}
};