如何从onChange函数中存储全局变量中的值？

var globalVariable = "";

function onChange(event) {
  globalVariable = event.target.value;
}

function createClosure() {
  var globalVariable = "";

  return function onChange(event) {
    globalVariable = event.target.value;
  }
}

var onChangeClosure = createClosure();

var eventManager = {
  subscribers: {},
  subscribe: function(event, callback) {
    if (!this.subscribers[event]) {
      this.subscribers[event] = [];
    }
    this.subscribers[event].push(callback);
  },
  publish: function(event, data) {
    if (this.subscribers[event]) {
      this.subscribers[event].forEach(function(callback) {
        callback(data);
      });
    }
  }
};

var globalVariable = "";

function onChange(event) {
  globalVariable = event.target.value;
  eventManager.publish('valueChanged', globalVariable);
}

eventManager.subscribe('valueChanged', function(value) {
  // Do something with the value
});