客户端服务器编程答案

【问题标题】：Client Server Programming客户端服务器编程
【发布时间】：2014-02-01 17:38:59
【问题描述】：

这里的代码完美地执行了所需的输出
它会检查条件并在条件不为真时打印错误，但即使条件为真且遵循但需要的输出，它也会打印。
在一个小的 if else 条件下发现问题
如何纠正

在下面的代码中if (fork() == 0) & if (!request.compare("") == 0)没有效果

/* Loop forever */ 
while (1) 
{
/* Accept a client connection */    
    clientFd = accept (serverFd, clientSockAddrPtr, (socklen_t*)&clientLen); 

//Fork child
    //if (fork() == 0) 
    {
    while(1)
    {   //Reads the client
            string request = read_Request (clientFd); 
        bool found = false;
        string response="Error !!! Country not found"; 
        //if (!request.compare("") == 0) 
        {

            for(vector<Country>::iterator it = countryData.begin(); it != countryData.end(); it++)
            {
        if(request.compare(it -> name) == 0) 
        {   
        string countryName = it -> name; 
        response += "\n";               
        response += it -> name; 
        response += "'s TLD Code"; 
        response += ((countryName).append("'s TLD Code")); 
        response += ": ";
        response += it -> TLDCode; 
        response += "\n";

        countryName = it -> name;
        response += it -> name;
        response += "'s FIPS104 Country Code"; 
        response += ((countryName).append("'s FIPS104 Country Code")); 
        response += ": ";
        response += it -> FIPS104CountryCode; 
        response += "\n";

        countryName = it -> name;
        response += it -> name;
        response += "'s ISO2 Country Code"; 
        response += ((countryName).append("'s ISO2 Country Code")); 
        response += ": ";
        response += it -> ISO2CountryCode; 
        response += "\n";

        countryName = it -> name; 
        response += it -> name; 
        response += "'s population"; 
        response += ((countryName).append("'s population")); 
        response += ": ";
        response += it -> population; 
        response += "\n";


            found = true;

            }
        }
}



write (clientFd, response.c_str(), strlen (response.c_str()) + 1);  
    }
    }

        close (clientFd); 
}

}

Here is the snip of output

在真假的情况下打印字符串响应。

有什么建议

【问题讨论】：

您的代码中没有任何内容打印字符串响应。它是不完整的。另外，这似乎不是 C：C 中没有字符串类型。
@ChrisJ.Kiick，我已经对代码进行了更改。

标签： c++ unix client-server serversocket fork

【解决方案1】：

好的，在这里你将一个字符串分配给变量response
String response="Error !!! Country not found";

然后在这里您将其他字符串连接到响应中，从而为您提供输出。

response += "\n";               
response += it -> name;

即错误！！！未找到国家 + \n + it->名称等

其次，正如@ChrisJ.Kiick 所说，你有一个神秘的 String 类型，它不是 c 语言的一部分

【讨论】：