如果使用 javascript 的 json 中所有元素均為 null，如何刪除對象

Question

您能告訴我如何使用 javascript 刪除 json 中所有空值的物件嗎？

我還需要刪除帶有 null/空鍵的巢狀物件。

{
    "glossary": {
        "title": "example glossary",
        "GlossDiv": {
            "title": "S",
              "text": null,
            "GlossList": {
                "GlossEntry": {
                    "ID": "SGML",
                    "SortAs": "SGML",
                    "GlossTerm": "Standard Generalized Markup Language",
                    "Acronym": "SGML",
                    "Abbrev": "ISO 8879:1986",
                    "GlossDef": {
                        "para": "A meta-markup language, used to create markup languages such as DocBook.",
                         "definition": null
                    },
                    "GlossSee": "markup",
                    "window": {
                        "title": "Sample Konfabulator Widget",
                        "description": ""
                    }
                }
            }
        },
        "image": {
            "src": null,
            "name": null,
            "alignment": null
        },
        "text": {
            "data": "Click Here",
            "size": null,
            "style": "bold",
            "name": "text1",
            "hOffset": "",
            "vOffset": "",
            "alignment": "center",
            "onMouseUp": null
        }
    }
}

需要輸出如下：

{
    "glossary": {
        "title": "example glossary",
        "GlossDiv": {
            "title": "S",
            "GlossList": {
                "GlossEntry": {
                    "ID": "SGML",
                    "SortAs": "SGML",
                    "GlossTerm": "Standard Generalized Markup Language",
                    "Acronym": "SGML",
                    "Abbrev": "ISO 8879:1986",
                    "GlossDef": {
                        "para": "A meta-markup language, used to create markup languages such as DocBook."
                    },
                    "GlossSee": "markup",
                    "window": {
                        "title": "Sample Konfabulator Widget"
                    }
                }
            }
        },
        "text": {
            "data": "Click Here",
            "style": "bold",
            "name": "text1",
            "alignment": "center"
        }
    }
}

如何遞歸地刪除整個 json 中帶有 null 或空鍵的物件。 就像 image 物件一樣，它的鍵具有空值或 null 值。

Answer 1

您可以在JSON.stringify(value, Replacer) / JSON.parse 中使用replacer/reviver 來獲得更接近的結果（文本，復活者）

使用 JSON.stringify 的範例

let data = {"glossary":{"title":"example glossary","GlossDiv":{"title":"S","text":null,"GlossList":{"GlossEntry":{"ID":"SGML","SortAs":"SGML","GlossTerm":"Standard Generalized Markup Language","Acronym":"SGML","Abbrev":"ISO 8879:1986","GlossDef":{"para":"A meta-markup language, used to create markup languages such as DocBook.","definition":null},"GlossSee":"markup","window":{"title":"Sample Konfabulator Widget","description":""}}}},"image":{"src":null,"name":null,"alignment":null},"text":{"data":"Click Here","size":null,"style":"bold","name":"text1","hOffset":"","vOffset":"","alignment":"center","onMouseUp":null}}}

let json = JSON.stringify(data, (key, value) => {
    return (value === null || value === '') ? undefined : value
}, 4)

console.log(json)