如何打印字典词典的内容？

Question

labels是字典词典：

{"1":{"id":"1","image":"1-0.png","name":"","xMax":"4802","xMin":"4770","yMax":"156","yMin":"141"},"2":{"id":"2","image":"1-0.png","name":"","xMax":"4895","xMin":"4810","yMax":"157","yMin":"141"},"3":{"id":"3","image":"1-0.png","name":"","xMax":"4923","xMin":"4903","yMax":"156","yMin":"145"},"4":{"id":"4","image":"1-0.png","name":"","xMax":"4956","xMin":"4931","yMax":"156","yMin":"145"}}

我想要的是：

for (i = 0; i < labels.length; i++){
    drawLabels(
      labels[i].id,
      labels[i].xMin,
      labels[i].xMax,
      labels[i].yMin,
      labels[i].yMax
    );
  }

我在主词典中有4个词典，所以我希望他们的内容逐一使用，但labels.length不能正常工作，甚至我正在访问下面的词典元素。

如何修复我的代码？

Answer 1

labels不是数组。

你应该这样做：

for (let i in labels){
    if(labels.hasOwnProperty(i)) {
        drawLabels(
            labels[i].id,
            labels[i].xMin,
            labels[i].xMax,
            labels[i].yMin,
            labels[i].yMax
        );
     }
}