function httpRequest(url, data = null, method = 'GET') {
    return new Promise((resolve, reject) => {
        let options = {
            method: method,
            headers: {
                'Content-Type': 'application/json'
            }
        };

        if (data) {
            options.body = JSON.stringify(data);
        }

        fetch(url, options)
          .then(response => {
                if (!response.ok) {
                    reject(new Error(`请求失败，状态码: ${response.status}`));
                } else if (response.status === 204) {
                    resolve(null);
                } else {
                    return response.json();
                }
            })
          .then(data => {
                resolve(data);
            })
          .catch(error => {
                reject(error);
            });
    });
}