(RSS源)未捕获类型错误:无法读取属性'title'的未定义

(RSS Feed) Uncaught TypeError: Cannot read property 'title' of undefined

本文关键字:读取 属性 未定义 title RSS 错误 类型      更新时间:2023-09-26

我正在尝试从Google Blogger Feed中挑选内容http://testdevchuli.blogspot.com/feeds/posts/default?redirect=false&orderby=已发布&alt=json在脚本中&callback=exeRSSpostReader&通过在http://testdevchuli.blogspot.com/您可以通过"检查元素"部分看到错误,其中只有一个红色警告…

Uncaught TypeError: Cannot read property 'title' of undefined
exeRSSpostReaderMain @ (index):1342
exeRSSpostReader @ (index):1313
(anonymous function) @ default?redirect=false&orderby=published&alt=json-in-script&callback=exeRSSpostReader&max-results=5…:2

那为什么会发生。。。???这是我的完整代码从上面的链接。。。

<script>
function exeRSSpostReader(json){
//<![CDATA[ 
//exeRSSpostReaderMain(json, DivisionId, Label, PostsVisible, ImageVisibility, SummaryVisibility, SummaryCharcters);
//DivisionId: Id of the division in which the result should shown.
//Label: Specific Label, Set &quot;&quot; for all posts.
//PostsVisible: No of posts shown in final result.
//ImageVisibility: Set true if you want thumbnails else set false.
//SummaryVisibility: Set true if you want summary else set false.
//SummaryCharcters: No of character shown in summary.
exeRSSpostReaderMain(json, 'latest_post', '', 3, true, true, 150);
exeRSSpostReaderMain(json, 'first_label', 'Dashain Song', 3, true, true, 150);
exeRSSpostReaderMain(json, 'second_label', 'Modern Song', 6, true, true, 150);
exeRSSpostReaderMain(json, 'third_label', 'Nepali Movie', 4, true, true, 150);
exeRSSpostReaderMain(json, 'fourth_label', 'Nepali Movie', 4, true, true, 150);
exeRSSpostReaderMain(json, 'fifth_label', 'Nepali Movie', 4, true, true, 150);
exeRSSpostReaderMain(json, 'sixth_label', 'Nepali Movie', 5, true, true, 150);
}
//]]>
</script>
<script style='text/javascript'>
//<![CDATA[ 
function exeRSSpostReaderMain(json, postArea, labelTxt, visiblePosts, imageVisible, summaryVisible, summaryChar) {
    var noOfTotalPosts  = 500;
    var outputDiv = postArea;
    var postLabel = labelTxt;
    var numPosts = json.feed.openSearch$totalResults.$t;
    var indexPosts = new Array();
    var pstChk = 0;
    var resultStr = '';
    var resultStr = '<ul style="height:100%;background:#fff;">';
    for (var i = 0; i < numPosts; ++i) {
        indexPosts[i] = i;
    }
    if (noOfTotalPosts > numPosts) {
        noOfTotalPosts = numPosts;
    }
    for (i = 0; i < noOfTotalPosts; ++i) {
        var entry = json.feed.entry[indexPosts[i]];
        var postTitle =  entry.title.$t;
        for (var k = 0; k <  entry.link.length; k++) {
            if ( entry.link[k].rel == 'alternate') {
                postURL =  entry.link[k].href;
                break;
            }
        }
        if ("content" in entry) {
            var postContent = entry.content.$t
        }
        s = postContent;
        a = s.indexOf("<img");
        b = s.indexOf("src='"", a);
        c = s.indexOf("'"", b + 5);
        d = s.substr(b + 5, c - b - 5);
        if ((a != -1) && (b != -1) && (c != -1) && (d != "")) {
            var imageUrl = d
        } else var imageUrl = 'https://lh6.googleusercontent.com/-cXUE46Oenac/U6rONTOCYuI/AAAAAAAAQTw/r_WI91TMLpk/s400/Images_no_image.gif';
        var img = '';
        if (imageVisible == true) {
        var img = '<a href="'+postURL+'"><img src="'+imageUrl+'" alt="' + postTitle + '" title="' + postTitle + '" /></a>';
        }
        var labels = '';
        if (!entry.category){
            var noLabel = "No Label In This Post";
        } else {
            for(var lblNo = 0; lblNo < entry.category.length; lblNo++){
                labels += entry.category[lblNo].term + ', ';
            }
        }
        if (labels.search(postLabel) >= 0 && pstChk < visiblePosts){
        resultStr += '<li><div id="exe_post_container">'  + img + '<h2 ><a href="'+postURL+'">' + postTitle + '</h2></a></h2><p>';
        var re = /<'S[^>]*>/g;
        postContent = postContent.replace(re, "");
        if (summaryVisible == true) {
            if (postContent.length < summaryChar) {
                resultStr += postContent + '</p>';
            } else {
                postContent = postContent.substring(0, summaryChar);
                var quoteEnd_gal = postContent.lastIndexOf(" ");
                postContent = postContent.substring(0, quoteEnd_gal);
                resultStr += postContent + '...</p>';
            }
        }
         resultStr += '</div></li>';
         pstChk++;
        }
    }
    resultStr += '</ul>';
    document.getElementById(outputDiv).innerHTML += resultStr;
}
function readMoreWidget() {
var var1 = document.getElementsByTagName('footer')[0].innerHTML;var var2 = var1.search('href="http://www.exeideas.net" target="_blank">EXEIdeas');if (var2 == '-1'){alert('This Template Is Designed By EXEIdeas(www.exeideas.net)');}
}
window.onload = readMoreWidget;
//]]>
</script>
<script src='http://testdevchuli.blogspot.com/feeds/posts/default?redirect=false&orderby=published&alt=json-in-script&callback=exeRSSpostReader&max-results=500'></script>

该错误是由于运行一个循环来获取RSS提要链接中更多的帖子。例如,如果你的RSS提要中有100篇文章,并且你正在运行一个101的循环,那么在运行第101次迭代时,它会在尝试从空空间获取数据时出错,所以尽量减少循环次数。