我需要观察变量myGlobalVar
。我需要检测并显示更改。
function AppViewModel() {
this.myVar = ko.observable(myGlobalVar);
}
// Activates knockout.js
ko.applyBindings(new AppViewModel());
<script src="https://cdnjs.cloudflare.com/ajax/libs/knockout/3.4.2/knockout-min.js"></script>
<script>myGlobalVar = "Foo";</script>
<p>Test: <strong data-bind="text: myVar"></strong></p>
<script>
setTimeout(function() {
myGlobalVar = "Bar";
console.log("myVar set to 'Bar'. Proof:");
console.log(myGlobalVar);
}, 1000);
</script>
在上面的示例代码中,我最初将window.test
设置为“ Foo”,然后在3秒钟后将其设置为“ Bar”,但是未检测到更改。
答案 0 :(得分:1)
您可以只更新observable而不是全局变量,为此,我举了一个例子,说明如何使用vm.myVar(value)在任何地方进行更改
如果您认为这样做无济于事,请三思而后行,可以使用一个间隔函数来设置当前全局变量,例如vm.myVar(myGlobalVar)
这就是为什么“可观察物”存在的原因 希望它真的有帮助;)
myGlobalVar = "Foo";
function AppViewModel() {
this.myVar = ko.observable(myGlobalVar);
}
// Activates knockout.js (you see i´m assigning var vm)
var vm = new AppViewModel();
ko.applyBindings(vm);
setTimeout(function() {
// edit the observable to update view
vm.myVar("Bar") ;
console.log("myVar set to 'Bar'. Proof:");
console.log(vm.myVar());
}, 1000);
<script src="https://cdnjs.cloudflare.com/ajax/libs/knockout/3.4.2/knockout-min.js"></script>
<script>myGlobalVar = "Foo";</script>
<p>Test: <strong data-bind="text: myVar"></strong></p>
答案 1 :(得分:0)
我能够解决“约翰·史密斯”(John Smith)的问题,我对其进行了更改以添加更改方法。我也可以只使用一个间隔,但是在这种情况下更改会更好。
myGlobalVar = "Foo";
function AppViewModel() {
this.myVar = ko.observable(myGlobalVar);
}
// Activates knockout.js (you see i´m assigning var vm)
var vm = new AppViewModel();
ko.applyBindings(vm);
setTimeout(function() {
// edit the observable to update view
vm.myVar("Bar") ;
console.log("myVar set to 'Bar'. Proof:");
console.log(vm.myVar());
}, 1000);
$("#globalVarField").change(function() {
myGlobalVar = $(this).val();
console.log("globalVarField changed to '"+ myGlobalVar + "'");
vm.myVar(myGlobalVar);
});
.as-console-wrapper { max-height: 100px !important; }
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/knockout/3.4.2/knockout-min.js"></script>
<script>myGlobalVar = "Foo";</script>
<p>Test: <strong data-bind="text: myVar"></strong></p>
Enter a value for myGlobalVar: <input type="text" id="globalVarField">