请问一下以下代码片段能否看出问题之所在

    
    var xmlHttp = null;
    if(window.ActiveXObject)
    {
        xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
    }
    else if(window.XMLHttpRequest)
    {
        xmlHttp = new XMLHttpRequest();
        
    }

var xmlHttp = null;
try {
    xmlHttp = new XMLHttpRequest();
} catch (MSIEx) {
    // Internet Explorer
    try {
        xmlHttp = new ActiveXObject("Msxml2.XMLHTTP");
    } catch (e) {
        try {
            xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
        } catch (e) {
            alert('您的浏览器不支持Ajax');
        }
    }
}