我有2个不同的嵌套对象,我需要知道它们是否在其中一个嵌套属性中有不同。
var a = {};
var b = {};
a.prop1 = 2;
a.prop2 = { prop3: 2 };
b.prop1 = 2;
b.prop2 = { prop3: 3 };
对象可以更复杂,有更多嵌套的属性。但这是一个很好的例子。我可以选择使用递归函数或lodash的东西…
我有2个不同的嵌套对象,我需要知道它们是否在其中一个嵌套属性中有不同。
var a = {};
var b = {};
a.prop1 = 2;
a.prop2 = { prop3: 2 };
b.prop1 = 2;
b.prop2 = { prop3: 3 };
对象可以更复杂,有更多嵌套的属性。但这是一个很好的例子。我可以选择使用递归函数或lodash的东西…
当前回答
下面是一个使用Lodash的简单解决方案:
_.differenceWith(a, b, _.isEqual);
注意,两个输入都需要是数组(可能是一个对象的数组)。
其他回答
As it was asked, here's a recursive object comparison function. And a bit more. Assuming that primary use of such function is object inspection, I have something to say. Complete deep comparison is a bad idea when some differences are irrelevant. For example, blind deep comparison in TDD assertions makes tests unnecessary brittle. For that reason, I'd like to introduce a much more valuable partial diff. It is a recursive analogue of a previous contribution to this thread. It ignores keys not present in a
var bdiff = (a, b) =>
_.reduce(a, (res, val, key) =>
res.concat((_.isPlainObject(val) || _.isArray(val)) && b
? bdiff(val, b[key]).map(x => key + '.' + x)
: (!b || val != b[key] ? [key] : [])),
[]);
BDiff允许检查期望值,同时容忍其他属性,这正是您想要的自动检查。这允许构建各种高级断言。例如:
var diff = bdiff(expected, actual);
// all expected properties match
console.assert(diff.length == 0, "Objects differ", diff, expected, actual);
// controlled inequality
console.assert(diff.length < 3, "Too many differences", diff, expected, actual);
回到完整的解决方案。使用bdiff构建一个完整的传统diff是很简单的:
function diff(a, b) {
var u = bdiff(a, b), v = bdiff(b, a);
return u.filter(x=>!v.includes(x)).map(x=>' < ' + x)
.concat(u.filter(x=>v.includes(x)).map(x=>' | ' + x))
.concat(v.filter(x=>!u.includes(x)).map(x=>' > ' + x));
};
在两个复杂对象上运行上述函数将输出类似于下面的内容:
[
" < components.0.components.1.components.1.isNew",
" < components.0.cryptoKey",
" | components.0.components.2.components.2.components.2.FFT.min",
" | components.0.components.2.components.2.components.2.FFT.max",
" > components.0.components.1.components.1.merkleTree",
" > components.0.components.2.components.2.components.2.merkleTree",
" > components.0.components.3.FFTResult"
]
最后,为了了解值之间的差异,我们可能需要直接eval() diff输出。为此,我们需要一个更丑的bdiff版本,输出语法正确的路径:
// provides syntactically correct output
var bdiff = (a, b) =>
_.reduce(a, (res, val, key) =>
res.concat((_.isPlainObject(val) || _.isArray(val)) && b
? bdiff(val, b[key]).map(x =>
key + (key.trim ? '':']') + (x.search(/^\d/)? '.':'[') + x)
: (!b || val != b[key] ? [key + (key.trim ? '':']')] : [])),
[]);
// now we can eval output of the diff fuction that we left unchanged
diff(a, b).filter(x=>x[1] == '|').map(x=>[x].concat([a, b].map(y=>((z) =>eval('z.' + x.substr(3))).call(this, y)))));
这将输出类似于下面的内容:
[" | components[0].components[2].components[2].components[2].FFT.min", 0, 3]
[" | components[0].components[2].components[2].components[2].FFT.max", 100, 50]
“一族”许可
深度比较使用模板的(嵌套)属性进行检查
function objetcsDeepEqualByTemplate(objectA, objectB, comparisonTemplate) {
if (!objectA || !objectB) return false
let areDifferent = false
Object.keys(comparisonTemplate).some((key) => {
if (typeof comparisonTemplate[key] === 'object') {
areDifferent = !objetcsDeepEqualByTemplate(objectA[key], objectB[key], comparisonTemplate[key])
return areDifferent
} else if (comparisonTemplate[key] === true) {
areDifferent = objectA[key] !== objectB[key]
return areDifferent
} else {
return false
}
})
return !areDifferent
}
const objA = {
a: 1,
b: {
a: 21,
b: 22,
},
c: 3,
}
const objB = {
a: 1,
b: {
a: 21,
b: 25,
},
c: true,
}
// template tells which props to compare
const comparisonTemplateA = {
a: true,
b: {
a: true
}
}
objetcsDeepEqualByTemplate(objA, objB, comparisonTemplateA)
// returns true
const comparisonTemplateB = {
a: true,
c: true
}
// returns false
objetcsDeepEqualByTemplate(objA, objB, comparisonTemplateB)
这将在控制台中工作。如果需要,可以添加数组支持
作为对亚当·博杜赫的回答的补充,这个问题考虑到了性质的差异
const differenceOfKeys = (...objects) =>
_.difference(...objects.map(obj => Object.keys(obj)));
const differenceObj = (a, b) =>
_.reduce(a, (result, value, key) => (
_.isEqual(value, b[key]) ? result : [...result, key]
), differenceOfKeys(b, a));
如果你需要知道哪些属性是不同的,使用reduce():
_.reduce(a, function(result, value, key) {
return _.isEqual(value, b[key]) ?
result : result.concat(key);
}, []);
// → [ "prop2" ]
var isEqual = function(f,s) {
if (f === s) return true;
if (Array.isArray(f)&&Array.isArray(s)) {
return isEqual(f.sort(), s.sort());
}
if (_.isObject(f)) {
return isEqual(f, s);
}
return _.isEqual(f, s);
};