Requirement: Basically I have an array of employee object in React JS, say empList. This empList contains primitive fields & again an inner array of another "address" objects, say addressList. I want to fetch data for all employees if they belong to city "ABC". They can have multiple address in city "ABC", but they should be fetched only once & pushed into finalList only once.

Problem : I am able to filter the employees having address in city "ABC" but in case, they have multiple address in city "ABC", then they are added to the finalList multiple times. So, I want to check for all addresses for an employee & in case, any one is found in city "ABC", I want to add it to finalList, break this inner map() function & go to outer map() to check for next employee.

Below is my code snippet.

var finalList =[];
empList.map(function(employee) {
           
            var valid = employee.addressList.map(function(address) {
                if (address.city.startsWith("ABC")) {
                    finalList.push(employee);
                    //Employee pushed to validList once, so now break from inner map() function & goto second line/execute on next employee object 
                  
                }
            });     //.slice(0,1); Slice doesn't work here since I want the condition to be true first, then break it.

CodePudding user response：

You can use the some which tests whether at least one element in the array passes the test condition.

Read about some here.

var finalList =  empList.filter(e => e.addressList.some(a => a.city.startsWith("ABC")));

Also I've updated your logic to use filter (instead of map) which creates a new array with all elements that pass the provided condition.

You can read about filter at here.