typescript将循环引用的对象数组转为字符串有问题，求解答

Question

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，结果应该返回的是一个数组里面有四个对象，但是其中两个却变为null，求解！谢谢！[{"id":"02c76c921d5011e987c600163e0e2174","code":"02c76c921d5011e987c600163e0e2174","fullTitle":"test,test-t","parentId":"e8bbcff61d4f11e987c600163e0e2174","_checked":false,"isChecked":false,"selected":false,"hovered":false,"expanded":true,"load":true,"parent":{"id":"e8bbcff61d4f11e987c600163e0e2174","code":"e8bbcff61d4f11e987c600163e0e2174","fullTitle":"test","parentId":0,"_checked":false,"isChecked":false,"children":[null,{"id":"2473dea61d5011e987c600163e0e2174","code":"2473dea61d5011e987c600163e0e2174","fullTitle":"test,test-e","parentId":"e8bbcff61d4f11e987c600163e0e2174","_checked":false,"isChecked":false,"selected":false,"hovered":false,"expanded":true,"load":true,"level":2,"isShow":true,"spaceHtml":"","hasChildren":false,"sort":"34","seq":2,"isLabelShow":true,"isInputShow":false,"showInput":false,"type":"editSort"}],"selected":false,"hovered":false,"expanded":true,"load":true,"parent":null,"level":1,"isShow":true,"spaceHtml":"","hasChildren":true,"sort":401,"seq":6,"isLabelShow":true,"isInputShow":false,"showInput":false},"level":2,"isShow":true,"spaceHtml":"","hasChildren":false,"sort":"234","seq":1,"isLabelShow":true,"isInputShow":false,"showInput":false,"type":"editSort"},null,{"id":"35f29a5e1d5011e987c600163e0e2174","code":"35f29a5e1d5011e987c600163e0e2174","fullTitle":"test-sun,test-u","parentId":"f24bd87b1d4f11e987c600163e0e2174","_checked":false,"isChecked":false,"selected":true,"hovered":false,"expanded":true,"load":true,"parent":{"id":"f24bd87b1d4f11e987c600163e0e2174","code":"f24bd87b1d4f11e987c600163e0e2174","fullTitle":"test-sun","parentId":0,"_checked":false,"isChecked":false,"children":[null,{"id":"0ef954591d5011e987c600163e0e2174","code":"0ef954591d5011e987c600163e0e2174","fullTitle":"test-sun,test-s","parentId":"f24bd87b1d4f11e987c600163e0e2174","_checked":false,"isChecked":false,"selected":false,"hovered":false,"expanded":true,"load":true,"level":2,"isShow":true,"spaceHtml":"","hasChildren":false,"sort":"456","seq":2,"isLabelShow":false,"isInputShow":true,"showInput":false,"type":"editSort"}],"selected":false,"hovered":false,"expanded":true,"load":true,"parent":null,"level":1,"isShow":true,"spaceHtml":"","hasChildren":true,"sort":402,"seq":7,"isLabelShow":true,"isInputShow":false,"showInput":false},"level":2,"isShow":true,"spaceHtml":"","hasChildren":false,"sort":"454","seq":1,"isLabelShow":true,"isInputShow":false,"showInput":false,"type":"editSort"},null]

Answer 1

当要处理的数据是循环引用的话，JSON.stringify是无法将数据转为字符串的，所以我目前就引用这个importcircularJsonfrom'circular-json';来处理数据会比较简单以下是处理之后的数据，看到属性parent被处理了[{"id":0,"code":0,"name":"save","status":"","remark":"","parentId":0,"_checked":false,"isChecked":false,"children":[{"id":0,"code":0,"name":"s","status":"","remark":"","parentId":0,"_checked":false,"isChecked":false,"children":[{"id":0,"code":0,"name":"ss","status":"","remark":"","parentId":0,"_checked":false,"isChecked":false,"selected":false,"hovered":false,"expanded":true,"load":true,"parent":"~0~children~0","level":3,"isShow":true,"spaceHtml":"","hasChildren":false,"seq":1,"sort":0,"isLabelShow":false,"isInputShow":true,"type":"insert"}],"selected":true,"hovered":false,"expanded":true,"load":true,"parent":"~0","level":2,"isShow":true,"spaceHtml":"","hasChildren":false,"seq":1,"sort":0,"isLabelShow":true,"isInputShow":false,"type":"insert"},{"id":0,"code":0,"name":"a","status":"","remark":"","parentId":0,"_checked":false,"isChecked":false,"selected":false,"hovered":false,"expanded":true,"load":true,"parent":"~0","level":2,"isShow":true,"spaceHtml":"","hasChildren":false,"seq":2,"sort":0,"isLabelShow":true,"isInputShow":false,"type":"insert"},{"id":0,"code":0,"name":"v","status":"","remark":"","parentId":0,"_checked":false,"isChecked":false,"selected":false,"hovered":false,"expanded":true,"load":true,"parent":"~0","level":2,"isShow":true,"spaceHtml":"","hasChildren":false,"seq":3,"sort":0,"isLabelShow":true,"isInputShow":false,"type":"insert"},{"id":0,"code":0,"name":"e","status":"","remark":"","parentId":0,"_checked":false,"isChecked":false,"selected":false,"hovered":false,"expanded":true,"load":true,"parent":"~0","level":2,"isShow":true,"spaceHtml":"","hasChildren":false,"seq":4,"sort":0,"isLabelShow":true,"isInputShow":false,"type":"insert"}],"selected":false,"hovered":false,"expanded":true,"load":true,"parent":null,"level":1,"isShow":true,"spaceHtml":"","hasChildren":false,"seq":33,"sort":0,"isLabelShow":true,"isInputShow":false,"type":"insert"}]

Answer 2

你把结果放出来没多大意义，你只是把你转换的方法发出来了，转换的对象却没有发出来。我猜测下，应该是你的那个判断的地方有问题if(cache.indexOf(value)!==-1){return;}这里如果存在这个缓存，你就直接return.这里return的是一个undefined.正常情况下，碰到undefined,symbol,function会自动省略，为了保持数组的索引位置信息，用null代替.查看youdontknowjs--JSONStringification