从函数内的函数返回try块的值

Question

我从另一个.js文件调用此函数，并且作为服务器的响应，有布尔值。

function submitFormData() {
    let var1 = '';
    submitForm();

    function makeRequest() {
        return new Promise((resolve, reject) => {
            let request = new XMLHttpRequest();
            request.withCredentials = true;
            request.open('POST', api);
            request.onreadystatechange = () => {
                if (request.readyState === 4) {
                    if (request.status >= 200 && request.status < 400) {
                        resolve(request.response);
                    } else {
                        reject(request.response);
                    }
                }
            };
            request.setRequestHeader('Content-Type', 'application/json');
            request.send();
        });
    }
    async function submitForm() {
        try {
            const requestPromise = makeRequest();
            const response = await requestPromise;
            return var1 = response
        }
        catch (errorResponse) {
            alert(errorResponse);
        };
    }
    return var1;
}

作为其他js文件中的值，我得到了空字符串，我不确定在这里我该怎么做。