I have an array of objects that has a nested array of objects in it. So the array looks something like:
const list = [
{
A: "a1",
B: "b1",
C: [
{
A: "a22",
B: "b12"
},
{
A: "a11",
B: "b11"
},
{
A: "a10",
B: "b10"
}
]
},
{
A: "a2",
B: "b2",
C: [
{
A: "a10",
B: "b10"
},
{
A: "a01",
B: "b01"
}
]
},
{
A: "a0",
B: "b0",
C: [
{
A: "a22",
B: "b22"
},
{
A: "a21",
B: "b21"
},
{
A: "a20",
B: "b20"
}
]
}
];
As can be seen I have an array of objects and each object as one or more fields that is also an array of objects. I can sort the array of objects based on one of the keys and it works just fine. What I want to do is sort by one of the keys in the nested array. For example sorting on C.A would yield something like (expected):
[
{
A: "a0",
B: "b0",
C: [
{
A: "a22",
B: "b22"
},
{
A: "a21",
B: "b21"
},
{
A: "a20",
B: "b20"
}
]
},
{
A: "a1",
B: "b1",
C: [
{
A: "a12",
B: "b12"
},
{
A: "a11",
B: "b11"
},
{
A: "a10",
B: "b10"
}
]
},
{
A: "a2",
B: "b2",
C: [
{
A: "a10",
B: "b10"
},
{
A: "a01",
B: "b01"
}
}
];
Ideas?
The way to get one's head clear on such things is to factor out the sort functions to explicitly state the objective, like this (I think I understand the objective)...
// sort a and b by the smallest value of A in their C arrays
const myCompare = (a, b) => {
return a.minAinC.localeCompare(b.minAinC);
};
// get the lexically smallest value of A in an object's C array
const minAinC = obj => {
const minC = obj.C.reduce((acc, o) => acc.A.localeCompare(o.A) > 0 ? o : acc, obj.C[0])
return minC.A;
};
// preprocess the outer array and cache a minAinC value on each, making the next sort efficient (optional)
const data = getData()
const readyToSort = data.map(o => ({ ...o, minAinC: minAinC(o) }));
const sorted = readyToSort.sort(myCompare)
console.log(sorted)
function getData() {
return [{
A: "a1",
B: "b1",
C: [{
A: "a22",
B: "b12"
},
{
A: "a11",
B: "b11"
},
{
A: "a10",
B: "b10"
}
]
},
{
A: "a2",
B: "b2",
C: [{
A: "a10",
B: "b10"
},
{
A: "a01",
B: "b01"
}
]
},
{
A: "a0",
B: "b0",
C: [{
A: "a22",
B: "b22"
},
{
A: "a21",
B: "b21"
},
{
A: "a20",
B: "b20"
}
]
}
];
}