I have this example :
var ex = {
"list_1": {
"money": 1000,
"manager": "Louis",
"cars": ["mazda", "ford_focus"]
},
"list_2": {
"money": 300,
"manager": "Keen",
"cars": ["fiat", "dacia"]
}
};
function updateFunction(option, id, prop, value) {
if (option == "update") {
if (prop == "money" && value != "") {
ex[id][prop] = value;
} else if (prop == "manager" && value != "") {
ex[id][prop] = value;
} else if (prop == "cars") {
ex[id][prop].push(value);
}
}
return ex;
};
updateFunction("update", "list_1", "manager", "Andrew");
console.log(ex)Now I want to include in the above function something to delete the first element from the cars array
example : updateFunction("delete","list_1","cars"......)
Result wanted : cars[ford_focus]
What should I do ? I tried some ideas from the net , but nothing doesn't work.
CodePudding user response：
You can delete the first element of an array using shift as
ex[id][prop].shift()
You can add custom validation according to your requirement. I've just added
if (prop === "cars")
because I know I'm dealing with an Array and I can use shift on an array object only
var ex = {
list_1: {
money: 1000,
manager: "Louis",
cars: ["mazda", "ford_focus"],
},
list_2: {
money: 300,
manager: "Keen",
cars: ["fiat", "dacia"],
},
};
function updateFunction(option, id, prop, value) {
if (option == "update") {
if (prop == "money" && value != "") {
ex[id][prop] = value;
} else if (prop == "manager" && value != "") {
ex[id][prop] = value;
} else if (prop == "cars") {
ex[id][prop].push(value);
}
} else if (option === "delete") {
if (prop === "cars") ex[id][prop].shift();
}
return ex;
}
//updateFunction("update", "list_1", "manager", "Andrew");
console.log(updateFunction("delete", "list_1", "cars"));/* This is not a part of answer. It is just to give the output fill height. So IGNORE IT */
.as-console-wrapper {
max-height: 100% !important;
top: 0;
}CodePudding user response：
You can use a filter() call and pass an array of indexes to filter against. This could easily be adapted to also delete by value.
function updateFunction(option, id, prop, value) {
...
if (option == "delete") {
if (prop == "cars") {
ex[id][prop] = ex[id][prop].filter((_, i) => !value.includes(i));
}
}
return ex;
};
updateFunction("delete","list_1","cars", [0, 2, 3])
Adapted to delete by either index or value.
function updateFunction(option, id, prop, value) {
...
if (option == 'delete') {
if (prop == 'cars') {
ex[id][prop] = ex[id][prop].filter((v, i) => !value.filter.includes(value.byValue ? v : i));
}
}
return ex;
};
updateFunction('delete', 'list_1', 'cars', { filter: [0, 2, 3], byValue: false });
updateFunction('delete', 'list_2', 'cars', { filter: ['fiat'], byValue: true });