Question

**为什么我收到此错误（并非所有代码路径都返回值）当我试图在函数中返回一些东西时我该如何解决它我需要返回值作为以下代码，但我无法做到这一点，因为这个错误可以帮助我**

public int return_order(string product_name)
{
    FileStream f1 = new FileStream("name.txt", FileMode.Open);
    StreamReader r1 = new StreamReader(f1);
    string name = r1.ReadLine();
    r1.Close();
    SqlConnection s = new SqlConnection("Data Source=(local);Initial Catalog=ShoppingOnline;Integrated Security=True");
    s.Open();
    SqlCommand d = new SqlCommand("Select * from Products where ProductName ='" + product_name + "'", s);
    SqlDataReader dr;
    dr = d.ExecuteReader();
    int i = 0;
    while (dr.Read())
    {
        i += 1;
    }
    dr.Close();
    if (i == 1)
    {
        Form3 f = new Form3();
        SqlCommand cmd = new SqlCommand("UPDATE Products SET Quantity = Quantity + 1 WHERE ProductName= @username ", s);
        cmd.Parameters.AddWithValue("@username", product_name);
        cmd.ExecuteNonQuery();
    }
    else
    {
        DateTime today = DateTime.Today;
        DateTime startdate = DateTime.UtcNow.Date;
        FileStream f = new FileStream("bill.txt", FileMode.Open);
        StreamReader r = new StreamReader(f);
        string q = r.ReadToEnd();
        string w = "";

        if (q.Contains(product_name))
        {
            while(r.ReadLine()!="EOO")
            {
                f.Position = 0;
                r.DiscardBufferedData();
                string enddate=r.ReadLine();
                f.Position = 0;
                r.DiscardBufferedData();
                while (r.Peek() != -1)
                {
                    DateTime dt = Convert.ToDateTime(enddate);  
                    DateTime dt2 = Convert.ToDateTime(startdate);

                    if ((dt2 - dt.Date).TotalDays < 14)
                    {
                        string temp = r.ReadLine();
                        if (temp == "Customer Name: " + name + "")
                        {
                            string record = r.ReadLine();
                            string[] fields = record.Split('@');
                            if (fields[0] == product_name)
                            {
                                w = fields[1];
                                SqlCommand cmd = new SqlCommand("insert into Products(ProductName,Price,Quantity) values('" + product_name + "','" + w + "','" + 1 + "')", s);
                                cmd.ExecuteNonQuery();
                                return 1;
                                break;
                            }
                        }
                    }
                    else 
                    { 
                        return -1; 
                    }//late
                }
                r.Close();
            }
        }
        else 
        { 
            return 2; 
        }//wrong
    }
}

Answer 1

我已使用提前退货简化了您的代码。并找到两个未定义的路径（见注释）。

我没有分析这段代码。只是通过扭转条件进行机械转换。（顺便说一句需要认真审查代码）

var http = require('http');

var map = require('through2-map');

uc = map(function(ch) {    
  return ch.toString().toUpperCase();  
});

server = http.createServer(function(request, response) {
  request.on('data',function(chunk){
      if (request.method == 'POST') {
         //change the data from request to uppercase letters and 
         //pipe to response. 
      }
    });
});
server.listen(8000);

当我试图返回某些内容时，并非所有代码路径都返回值错误

1 个答案: