javascript - 这个函数是做什么的？我对读写部分最困惑

Question

我知道这是一个构造函数，但我没有得到读写部分。我知道它有一个 if 和 else 语句，但我对它在做什么感到困惑!

 self.CondInspecChks_RevValve_UI = ko.computed({      
         read: function () {
             return self.CondInspecChks_RevValve() == 1 ? true : false;
        },
        write: function (newValue) {
            self.CondInspecChks_RevValve(newValue ? 1 : 0);
        }
    });

Answer 1

这是一个Knockout computed observable - 它允许将动态值分配给 KO observable .

const normalObservable = ko.observable("hello");
const computedObservable = ko.computed(function() {
  return "my dynamic value is: " + normalObservable();
})

console.log(normalObservable())
console.log(computedObservable())

//update the observable
normalObservable("world");

console.log(normalObservable())

//the computed also changed
console.log(computedObservable())

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在这种特殊情况下，这是使用计算的高级构造使其成为 writeable computed .

const someWriteableValue = ko.observable("hello")

const computed = ko.computed({
    read: function () {
        return "my dynamic value is: " + someWriteableValue();
    },
    write: function (value) {
       someWriteableValue(value);
    }
})

console.log(computed());

//update the computed
computed("world");

console.log(computed());

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