javascript Angular - 只有在唯一时才推送到数组
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Angular - Only push to array if unique
提问by xXPhenom22Xx
I have an Angular application that collects values of items for an invoice, I want to make sure only unique items are being added to this collection but am having no luck.
我有一个 Angular 应用程序，它收集发票项目的价值，我想确保只有唯一的项目被添加到这个集合中，但我没有运气。
I am pushing 3 pieces of information to this collection: id, price, and type. I want to make sure there is nothing in the collection currently matching those 3 points.
我正在向这个集合推送 3 条信息：id、价格和类型。我想确保当前收藏中没有与这 3 点匹配的内容。
// My container
$scope.invoice = {
items: [{
}]
}
$scope.addPhoto = function() {
console.log('Withdrawing Photo: '+ $scope.item.id);
if ($scope.invoice.items.indexOf(item.id) != $scope.item.id)
{
$scope.invoice.items.push({
id: $scope.item.id,
price: $scope.item.price,
type: 'photo'
});
}
}
// Trying to avoid collections like this
// 尽量避免这样的集合
invoice: { items: [ { } , { id: 25 price: 0 type: photo } , { id: 25 price: 0 type: photo } ] }
发票：{ 项目：[ { } , { id: 25 price: 0 type: photo } , { id: 25 price: 0 type: photo } ] }
采纳答案by xXPhenom22Xx
This is the solution I came up with to solve my problem, hopefully it helps someone else.
这是我想出的解决方案来解决我的问题，希望它可以帮助其他人。
$scope.addPhoto = function () {
console.log('Withdrawing Photo: ' + $scope.item.id);
var newItemId = $scope.item.id;
var newItemPrice = $scope.item.price;
var newItemType = 'photo';
var matches = true;
// Make sure user hasnt already added this item
angular.forEach($scope.invoice.items, function(item) {
if (newItemId === item.id && newItemPrice === item.price && newItemType === item.type) {
matches = false;
$scope.message = 'You have already selected to withdraw this item!';
}
});
// add item to collection
if (matches != false) {
$scope.invoice.items.push({
id: $scope.item.id,
price: $scope.item.price,
type: 'photo'
});
$scope.total += $scope.item.price;
$scope.message = 'Total Amount Selected';
}
};
回答by SomeKittens
.filteris pretty much what you need.
.filter几乎是您所需要的。
$scope.addPhoto = function() {
console.log('Withdrawing Photo: '+ $scope.item.id);
var matches = $scope.invoice.items.filter(function(datum) {
return datum.id === $scope.item.id &&
datum.price === $scope.item.price &&
datum.type === $scope.item.type;
});
if (!matches.length)
{
$scope.invoice.items.push({
id: $scope.item.id,
price: $scope.item.price,
type: 'photo'
});
}
}
回答by Taran
YOu can simple pop opposite of push
你可以简单的弹出相反的推送
array.splice(array.pop(item));
