如何在 JS 中循环遍历复杂的 object

Question

这是我的 obj，我只想遍历它并显示错误：

var obj = {
    "error": {
        "errors": {
            "username": {
                "properties": {
                    "message": "username field is empty.",
                    "type": "required",
                    "path": "username"
                },
                "kind": "required",
                "path": "username"
            },
            "email": {
                "properties": {
                    "message": "email field is empty.",
                    "type": "required",
                    "path": "email"
                },
                "kind": "required",
                "path": "email"
            },
            "password": {
                "properties": {
                    "message": "password field is empty.",
                    "type": "required",
                    "path": "password"
                },
                "kind": "required",
                "path": "password"
            }
        },
        "_message": "User validation failed",
        "message": "User validation failed: username: username field is empty., email: email field is empty., password: password field is empty."
    }
}

我想显示错误： properties.message但我很难过，这是我迄今为止尝试过的：

for (var key in obj.error.errors) {
    for (var key2 in key.properties){
        for (var key3 in key2.message){
            console.log(key3)
        } 
    } 
}

但是控制台是空白的。

Answer 1

在循环中，您得到的是密钥，而不是 object 本身。 此外，如果您的数据是这样的结构，您也不需要添加所有这些循环。 只需选择错误，遍历所有错误。

for(var d in obj.error.errors){
    console.log(a[d].properties.message)
}

Answer 2

一个可行的解决方案

Object.values(obj.error.errors).forEach((error) => { console.log(error.properties.message) })

查看您的数据结构，您只需要迭代“错误”列表

Answer 3

检查一下，它将以properties:message格式返回您

 const obj = { "error": { "errors": { "username": { "properties": { "message": "username field is empty.", "type": "required", "path": "username" }, "kind": "required", "path": "username" }, "email": { "properties": { "message": "email field is empty.", "type": "required", "path": "email" }, "kind": "required", "path": "email" }, "password": { "properties": { "message": "password field is empty.", "type": "required", "path": "password" }, "kind": "required", "path": "password" } }, "_message": "User validation failed", "message": "User validation failed: username: username field is empty., email: email field is empty., password: password field is empty." } }; const objVal = Object.values(obj.error.errors); const errors = objVal.reduce((obj, item) => { return (obj[item.path] = item.properties.message, obj) },{}) console.log(errors);