剑道DataSource requestEnd事件被多次激发

let isBound = false;

function bindRequestEndEvent() {
  if (!isBound) {
    dataSource.on('requestEnd', handleRequestEnd);
    isBound = true;
  }
}

function unbindRequestEndEvent() {
  if (isBound) {
    dataSource.off('requestEnd', handleRequestEnd);
    isBound = false;
  }
}

function debounce(func, wait) {
  let timeout;
  return function(...args) {
    clearTimeout(timeout);
    timeout = setTimeout(() => func.apply(this, args), wait);
  };
}

const debouncedHandleRequestEnd = debounce(handleRequestEnd, 300);

dataSource.on('requestEnd', debouncedHandleRequestEnd);

let currentRequest = null;

function fetchData() {
  if (currentRequest) {
    currentRequest.cancel();
  }
  currentRequest = dataSource.fetchData().then(response => {
    // 处理响应
  }).catch(error => {
    // 处理错误
  });
}