C# 异步任务中的大量ping-获取异常“异步调用已在进行中。”
我发布了之前的一个问题,我发现了一种使用线程的工作方法——但当在线程之间重写变量时,它会导致可靠性问题。有人指出我要使用ping async和tasks,但我得到了以下例外:C# 异步任务中的大量ping-获取异常“异步调用已在进行中。”,c#,.net,asynchronous,task-parallel-library,ping,C#,.net,Asynchronous,Task Parallel Library,Ping,我发布了之前的一个问题,我发现了一种使用线程的工作方法——但当在线程之间重写变量时,它会导致可靠性问题。有人指出我要使用ping async和tasks,但我得到了以下例外: Error: System.InvalidOperationException: An asynchronous call is already in progress. It must be completed or canceled before you can call this method. 它专门指向Wait
Error: System.InvalidOperationException: An asynchronous call is already in progress. It must be completed or canceled before you can call this method.
它专门指向Wait PingAsyncHostList和Wait Task.WhenAlltasks
代码如下:
MySqlConnection Connection = new MySqlConnection(ConnectionString);
Connection.Open();
MySqlCommand query = Connection.CreateCommand();
query.CommandText = "SELECT obj_id AS id,ip FROM objects LIMIT 15";
MySqlDataReader Nodes = query.ExecuteReader();
// Record in log that a NEW iteration is starting - for tracking issues with pings
Library.WriteErrorLog("######################## New Iteration ########################");
var HostList = new List<HostObject>();
int i = 1;
while (Nodes.Read())
{
var Host = new HostObject();
Host.HostName = Nodes["ip"].ToString();
Host.HostID = Nodes["id"].ToString();
HostList.Add(Host);
i++;
}
Connection.Close();
var results = await PingAsync(HostList);
bool WaitingOnPings = false;
while (WaitingOnPings == false)
{
if (results != null)
{
foreach (PingReply result in results)
{
Library.WriteErrorLog(result.Status.ToString());
}
WaitingOnPings = true;
}
else
{
Thread.Sleep(500);
}
}
以及:
谢谢你的帮助 Ping可能不打算用于多个并发请求。尝试为每个主机创建一个新的Ping对象
private async Task<List<PingReply>> PingAsync(List<HostObject> HostList)
{
var tasks = HostList.Select(HostName => new Ping().SendPingAsync(HostName.ToString(), 2000));
var results = await Task.WhenAll(tasks);
return results.ToList();
}
我认为这是朝着正确的方向迈出的一步,但现在我遇到了错误:System.Net.NetworkInformation.PingException:Ping请求期间发生异常。-->System.Net.Sockets.SocketException:没有已知的此类主机正在检查字符串,这是一个有效的ipv4地址。在没有异步的情况下执行此操作时使用的相同字符串。列表中的示例ip:10.60.138.1。有什么想法吗?谢谢我得到了它,必须选择HostObject并使用HostOjbect.HostName。谢谢你的帮助!
private async Task<List<PingReply>> PingAsync(List<HostObject> HostList)
{
var tasks = HostList.Select(HostName => new Ping().SendPingAsync(HostName.ToString(), 2000));
var results = await Task.WhenAll(tasks);
return results.ToList();
}