javascript - 如何在订阅功能中取消订阅放大？

Question

amplify.subscribe("WorkTypesReceived", function () {

    var workTypesList = amplify.store("ExpenseWorkTypesFor" + JobNo_);
    amplify.unsubscribe("WorkTypesReceived");

});

getDropdownExpenseWorkTypes(JobNo_);

我getDropdownExpenseWorkTypes调用了一个在完成时发布的函数"WorkTypesReceived"。但由于我在一个页面上不止一次调用整个函数，它呈指数级增长（同一主题的多个订阅）。我想在订阅发布一次后删除订阅（因此进入订阅功能一次）。

该行amplify.unsubscribe("WorkTypesReceived")似乎不起作用，文档说我需要第二个参数作为回调函数。但我在回调函数内部，所以不确定如何继续。

Answer 1

如果您在回调中添加名称，您可以使用它来取消订阅...

amplify.subscribe( "WorkTypesReceived", function storeWork() {
    var workTypesList = amplify.store( "ExpenseWorkTypesFor" + JobNo_ );
    amplify.unsubscribe( "WorkTypesReceived", storeWork );
});