javascript - 如何将 for key value 与 while 循环结合起来？

Question

每当对象数组和 JSON 文本键匹配时，我都会尝试控制台日志 test。

它将记录对象数组内的每个标签，但 while 循环无法按预期工作。

一个工作示例:http://codepen.io/Caspert/pen/PZYjPV?editors=001

var text_buffer = raw_content.text;

var raw_content = {
    "text": "Test image 1 [image] Test image 2 [image] Test image 3 [image] Test image 4 [image]",
    "media": [{
        "image": {
            "src": "http://placehold.it/400x200",
            "caption": "This is a caption"
        }
    }, {
        "image": {
            "src": "images/gallery/sh0.png",
            "caption": "This is a caption"
        }
    }, {
        "image": {
            "src": "http://placehold.it/400x200",
            "caption": "This is a caption"
        }
    }, {
        "image": {
            "src": "images/gallery/sh0.png",
            "caption": "This is a caption"
        }
    }]
};

// Find multiple tags
var tags = {
    "image": '[image]',
    "gallery": '[gallery]'
};

for (var key in tags) {
    if (tags.hasOwnProperty(key)) {
        var tag = tags[key];
        console.log('tag = ', tag);

        while (text_buffer.indexOf(tag) !== -1) {
            console.log('test');
        }
    }
};

Answer 1

您的 while 循环将挂起，因为 indexOf 将始终搜索 tag 变量的第一个实例，该实例始终存在。解决此问题的最佳方法是指定要搜索的起始索引:

var startIndex = -1;

while ((startIndex = raw_content.text.indexOf(tag, startIndex + 1)) != -1) {
  console.log('test');
}

看看这个example fiddle .