Javascript 代码会运行，因为它会发出ajax请求，然后继续运行。任何依赖于quotarray的内容都应该在$.ajax的success函数中

当您在控制台中键入

quotarray.length

时，数组有一个长度，这仅仅是因为此时Ajax请求已经完成。

什么是

rotationArray

以及如何重置循环？您如何准确声明此数组？如果未使用

var quotarray=[]定义“quotarray”，则切到它;或
var quotarray=new Array（）
那么它可能根本不是数组。rotationArray是一个存储为每个周期生成的随机数的数组。quoteArray声明如下：var quoteArray=new array（）；我确信数组长度被正确找到，因为我还使用了console.log（quoteArray.length），它返回的数字大于0。quoteArray.length将取决于函数循环的次数。我不是在写“console.log（randomnumber）”在firebug中，我只是在代码中内联编写了它，所以每次它在while循环中迭代时，我都会得到“randomnumber”是什么的读数。@用户是的，即使是这样。设置
async:false
将导致浏览器阻止所有其他内容，但
$之后的脚本仍将运行。ajax
仍将运行。
async:false
通常是ally不是您要找的。@用户，如果您放入
console.log（quoteArray.length）在同一个循环中，你应该得到
0
@box9谢谢你的澄清！我有一个错误的印象。我猜另一件事是a）这个函数在页面加载后15秒才运行，b）通过firebug查看ajax请求，在运行之前它们都已完成，所以我理解你的意思回答：我不明白它在这种情况下是如何应用的。同样值得注意的是：如果我一开始没有说清楚，这个脚本有时会成功运行（在Chrome、Firefox和IE中）。我似乎只有在Firefox和IE中存在无限循环的问题，但在Chrome中没有。
quoteArray[1] = "some text"
quoteArray[2] = "some different text"
quoteArray[3] = "text again"
quoteArray[4] = "completely different text"
quoteArray[5] = "ham sandwich"

//Note: at this point in the function I have generated a random number once already and stored it in 'randomnumber'
//I use this while statement to evaluate 'randomnumber' until the condition of it NOT being a number that has already been used and NOT being the last number is met.
while(randomnumber === rotationArray[randomnumber] || randomnumber === lastnumber){
    randomnumber = Math.floor(Math.random() * (quoteArray.length));
}

// Function to initialize the quoteObj
    function quoteObj(text,cname,ccompany,url,height) {
            this.text=text;
            this.cname=cname;
            this.ccompany=ccompany;
            this.url=url;
            this.height=height;
        }

// Populate my quotes Object with the quotation information from the XML sheet. 

    var qObj = new quoteObj('','','','');
    var quoteArray = new Array();
    var counter = 0;

//cycles through each XML item and loads the data into an object which is then stored in an array
    $.ajax({
        type: "GET",
        url: "quotes.xml",
        dataType: "xml",
        success: function(xml) {
            $(xml).find('quote').each(function(){
                quoteArray[counter] = new quoteObj('','','','');
                console.log(quoteArray[counter]);
                quoteArray[counter].text = $(this).find('text').text();
                quoteArray[counter].cname = $(this).find('customer_name').text();
                quoteArray[counter].ccompany = $(this).find('customer_company').text();
                quoteArray[counter].url = $(this).find('project').text();
                ++counter;
            });
        }
    });

// This is the setion that is generating my infinite loop issue.
// I've included all of the other code in case people are wondering specific things about how an item was initialized, etc. 

// Generate a random first quote then randomly progress through the entire set and start all over.      

    var randomnumber = Math.floor(Math.random() * (quoteArray.length));
    var rotationArray = new Array(quoteArray.length);
    var v = 0;
    var lastnumber = -1;

    bHeight = $('#rightbox').height() + 50;
    var cHeight = 0;
    var divtoanim = $('#customerquotes').parent();

//NOT RELATED// 
// Give the innershadow a height so that overflow hidden works with the quotations. 
    $(divtoanim).css({'height' : bHeight});

// Rotate the Quotations Randomly function. 
    setInterval(function(){     
        randomnumber = Math.floor(Math.random() * (quoteArray.length));

//checks to see if the function loop needs to start at the beginning. 
        if(v == (quoteArray.length)){
            rotationArray.length = 0;
            v = 0;
        }
//determines if the random number is both different than any other random number generated before and that is is not the same as the last random number
        while(randomnumber === rotationArray[randomnumber] || randomnumber === lastnumber){
            randomnumber = Math.floor(Math.random() * (quoteArray.length));
        }   

        lastnumber = randomnumber;
        rotationArray[randomnumber] = randomnumber;
        ++v;

//NOT RELATED//
//animation sequence
        $('#ctext, #cname').animate({'opacity':'0'},2000, function(){
            $('#ctext').html(quoteArray[randomnumber].text);
            $('#cname').html('- ' + quoteArray[randomnumber].cname);

            cHeight = $('#customerquotes').height() + 50;
            adjustHeight(bHeight,cHeight,divtoanim);

            $('#ctext').delay(500).animate({'opacity':'1'},500);
            $('#cname').delay(1500).animate({'opacity':'1'},500);
        });
    },15000);
Math.floor(Math.random() * (5));

var results = ['some text','some text2','some text3','some text4','some text5', /* ...etc */ ],
       randomable = results;

function getRandomOffset( arr )
{
    var offset,
           len;

    if( arr.length < 1 )
        return false;
    else if( arr.length > 1 )
        offset = Math.floor(Math.random() * arr.length );
    else
        offset = 0;

    arr.splice( offset, 1 );

    return [
        offset,
        arr
    ];

}

while( res = getRandomOffset( randomable ) )
{
    // Set the randomable for next time
    randomable = res[1];
    // Do something with your resulting index
    results[ res[0] ];
}