| 12345678910111213141516171819202122232425262728293031 | async function signUp(username, password) {    try {        const response = await fetch('http://localhost:3000/signup', {            method: 'POST',            headers: {                'Content-Type': 'application/json'            },            body: JSON.stringify({                username,                password            })        });        const data = await response.json();                if (!response.ok) {            throw new Error(data.error || '注册失败');        }        console.log('注册成功:', data.message);        return data;    } catch (error) {        console.error('注册错误:', error.message);        throw error;    }}// 使用示例signUp('newuser', 'password123')    .then(() => console.log('注册流程完成'))    .catch(() => console.log('注册流程失败'));
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