2-7 js基础-ajax封装

function json2url(json) {
    var arr = [];
    for (var name in json) {
        arr.push(name+'='+encodeURIComponent(json[name]));
    }
    return arr.join('&');
}
function ajax(json) {
    json.data = json.data || {};
    json.data.t = Math.random();
    json.type = json.type || 'GET';
    if (window.XMLHttpRequest) {
        var oAjax = new XMLHttpRequest();
    } else {
        var oAjax = new ActiveXObject('Microsoft.XMLHTTP');
    }
    switch (json.type.toLowerCase()) {
        case 'get':
            oAjax.open('GET', json.url + '?' + json2url(json.data), true);
            oAjax.send();
            break;
        case 'post':
            oAjax.open('POST', json.url, true);
            oAjax.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
            oAjax.send(json2url(json.data));
    }
    oAjax.onreadystatechange = function () {
        if (oAjax.readyState == 4) {
            if (oAjax.status >= 200 && oAjax.status < 300 || oAjax.status == 304) {
                json.success && json.success(oAjax.responseText);
            } else {
                json.erro && json.erro(oAjax.status);
            }
        }
    };
}