如何检查 JavaScript 对象数组中是否存在特定对象？

Question

How do I check if a particular object exist or not in a JavaScript array of objects?

// Main array of objects
var dailogMappingData = [
    {
        "name": "AgglomerativeCluster",
        "size": 3938
    }, {
        "name": "CommunityStructure",
        "size": 3812
    }, {
        "name": "HierarchicalCluster",
        "size": 6714
    }
];


// search object to find in the above array is exist or not: 
var findObj = {
    "name": "CommunityStructure",
    "size": 3812
};


var m, n;

for (m = 0; m < this.dailogMappingData.length; m++) {
    for (n = 0; n < mapKeys.length; n++) {
        if (this.dailogMappingData[m][mapKeys[n]] === newObj[mapKeys[n]]) {
            isInArray = true;
        } else {
            isInArray = false;
        }

    }
    if (isInArray) {
        break;
    }
}

How to find an object in an array, or find out if it exists or not?

Answer 1

if name property is unique you can simply check if there are any objects in array with the same name:

 var dailogMappingData = [{ "name": "AgglomerativeCluster", "size": 3938 }, { "name": "CommunityStructure", "size": 3812 }, { "name": "HierarchicalCluster", "size": 6714 }]; var findObj = { "name": "CommunityStructure", "size": 3812 }; const isInArray = dailogMappingData.some(item => item.name === findObj.name); console.log(isInArray);

If you can't rely on name property and need to compare all properties, you may want to use isEqual function from Lodash

 var dailogMappingData = [{ "name": "AgglomerativeCluster", "size": 3938 }, { "name": "CommunityStructure", "size": 3812 }, { "name": "HierarchicalCluster", "size": 6714 }]; var findObj = { "name": "CommunityStructure", "size": 3812 }; const isInArray = dailogMappingData.some(item => _.isEqual(findObj, item)); console.log(isInArray);

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