node+express POST請求

//  POST 登錄
app.post('/login', function (req, res) {
  // 定義了一個post變量，用於暫存請求體的信息
  let [post,addSql,addSqlParams] = ['','',[]]
  // 通過req的data:數據加載,事件監聽函數，每當接受到請求體的數據，就累加到post變量中
  req.on('data', function(chunk){    
      post += chunk;
      let obj = eval('(' + post.toString()  + ')');
      console.log(post)
     let [name,password] = [obj.name,obj.password];
      addSql = 'SELECT id FROM user WHERE name=? and password=?';
      addSqlParams = [name,password]
      post = obj;
  });