救命

Question

 //加载DLL函数,EntryPoint="OpenCom_R")
        [DllImport(@"D:\XiongWei\TDODLL30.dll")]        private static extern int OpenCom_R(long ComPort);
        private void Form1_Load(object sender, EventArgs e)
        {
           
        }        private void button1_Click(object sender, EventArgs e)
        {
             int num = ComPort;
              
             if(num==0)
            {
            //成功
                this.textBox1.Text = "成功";               
            }
            else if (num==1)
            {
                //失败
            }
            else if(num==2)
            {
                //占用
            
            }
         }ComPort  不存在？
怎么回事？？

Answer 1

ComPort; 在哪定义了？应该： int num = OpenCom_R(???); 

Answer 2

 OpenCom_R(long ComPort);和ComPort不一样吧，要一样再试试

Answer 3

ComPort 这个不是应该在DLL里面有么？
  还要定义？不懂

Answer 4

方法搞错了！
int num = OpenCom_R(参数);
 OpenCom_R(参数)只有这个方法才返回一个int类型数据！