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
此解决方案返回一个具有修改过的属性的对象。
_.reduce(a, (r, v, k) => { return _.merge(r, _.isEqual(v, b[k]) ? {} : { [k]: v }); }, {});
其他回答
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
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
简单使用_。isEqual方法,它将适用于所有比较…
注意:此方法支持比较数组、数组缓冲区、 布尔值、 *日期对象,错误对象,地图,数字,对象对象,正则表达式, *集合、字符串、符号和类型化数组。对象对象进行比较 *通过自身的,不可继承的,可枚举的属性。函数和DOM *节点不支持。
所以如果你有以下情况:
const firstName = {name: "Alireza"};
const otherName = {name: "Alireza"};
如果是:_。isEqual (firstName, otherName);
它会返回true
如果const fullName = {firstName: "Alireza", familyName: "Dezfoolian"};
如果是:_。isEqual (firstName, fullName);
将返回false
我们需要在两个json更新之间获取delta,以跟踪数据库更新。也许其他人会觉得这很有用。
https://gist.github.com/jp6rt/7fcb6907e159d7851c8d59840b669e3d
const {
isObject,
isEqual,
transform,
has,
merge,
} = require('lodash');
const assert = require('assert');
/**
* Perform a symmetric comparison on JSON object.
* @param {*} baseObj - The base object to be used for comparison against the withObj.
* @param {*} withObj - The withObject parameter is used as the comparison on the base object.
* @param {*} invert - Because this is a symmetric comparison. Some values in the with object
* that doesn't exist on the base will be lost in translation.
* You can execute again the function again with the parameters interchanged.
* However you will lose the reference if the value is from the base or with
* object if you intended to do an assymetric comparison.
* Setting this to true will do make sure the reference is not lost.
* @returns - The returned object will label the result of the comparison with the
* value from base and with object.
*/
const diffSym = (baseObj, withObj, invert = false) => transform(baseObj, (result, value, key) => {
if (isEqual(value, withObj[key])
&& has(withObj, key)) {
return;
}
if (isObject(value)
&& isObject(withObj[key])
&& !Array.isArray(value)) {
result[key] = diffSym(value, withObj[key], invert);
return;
}
if (!invert) {
result[key] = {
base: value,
with: withObj[key],
};
return;
}
if (invert) {
result[key] = {
base: withObj[key],
with: value,
};
}
});
/**
* Perform a assymmetric comparison on JSON object.
* @param {*} baseObj - The base object to be used for comparison against the withObj.
* @param {*} withObj - The withObject parameter is used as the comparison on the base object.
* @returns - The returned object will label the values with
* reference to the base and with object.
*/
const diffJSON = (baseObj, withObj) => {
// Deep clone the objects so we don't update the reference objects.
const baseObjClone = JSON.parse(JSON.stringify(baseObj));
const withObjClone = JSON.parse(JSON.stringify(withObj));
const beforeDelta = diffSym(baseObjClone, withObjClone);
const afterDelta = diffSym(withObjClone, baseObjClone, true);
return merge(afterDelta, beforeDelta);
};
// By Example:
const beforeDataObj = {
a: 1,
c: { d: 2, f: 3 },
g: 4,
h: 5,
};
const afterDataObj = {
a: 2,
b: 3,
c: { d: 1, e: 1 },
h: 5,
};
const delta = diffJSON(beforeDataObj, afterDataObj);
// Assert expected result.
assert(isEqual(delta, {
a: { base: 1, with: 2 },
b: { base: undefined, with: 3 },
c: {
d: { base: 2, with: 1 },
e: { base: undefined, with: 1 },
f: { base: 3, with: undefined },
},
g: { base: 4, with: undefined },
}));
如果你只需要键比较:
_.reduce(a, function(result, value, key) {
return b[key] === undefined ? key : []
}, []);