i am using a method to retrieve data from an OPC DA server using TitaniumAS packages, the problem i am having is that i have a lot of tags to read/write so i have to use methods. The WriteX method works fines as it doesnt have to return anything but the read does not, well it does its job, it reads but i cannot use that data outside of the method because it was a void method, when i tried to use it as a String method (that's the type of data i need) it says :
Error CS0161 'ReadX(string, string)': not all code paths return a value
PS : note that i am just a beginner in C#
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using TitaniumAS.Opc.Client.Common;
using TitaniumAS.Opc.Client.Da;
using TitaniumAS.Opc.Client.Da.Browsing;
using System.Threading;
using System.Threading.Channels;
using Async;
namespace OPCDA
{
class Program
{
static void Main(string[] args)
{
TitaniumAS.Opc.Client.Bootstrap.Initialize();
Uri url = UrlBuilder.Build("Kepware.KEPServerEX.V6");
using (var server = new OpcDaServer(url))
{
server.Connect();
OpcDaGroup group = server.AddGroup("MyGroup");
group.IsActive = true;
Ascon ascon1 = new Ascon();
ReadX("Channel1.Ascon1.AsconS", ascon1.ALM);
Console.WriteLine("value = {0}", ascon1.ALM);
void WriteX(String Link, String Ascon)
{
var definition1 = new OpcDaItemDefinition
{
ItemId = Link,
IsActive = true
};
OpcDaItemDefinition[] definitions = { definition1 };
OpcDaItemResult[] results = group.AddItems(definitions);
OpcDaItem tag = group.Items.FirstOrDefault(i => i.ItemId == Link);
OpcDaItem[] items = { tag };
object[] Values = { Ascon };
HRESULT[] Results = group.Write(items, Values);
}
string ReadX(String Link, String read)
{
var definition1 = new OpcDaItemDefinition
{
ItemId = Link,
IsActive = true
};
OpcDaItemDefinition[] definitions = { definition1 };
OpcDaItemResult[] results = group.AddItems(definitions);
OpcDaItemValue[] values = group.Read(group.Items, OpcDaDataSource.Device);
read = Convert.ToString(values[0].Value);
}
}
}
}
}
CodePudding user response:
the first step was to state the return like this :
return Convert.ToString(values[0].Value)
instead of read = Convert.ToString(values[0].Value)
then go up and use that value with my variable :
ascon1.ALM=ReadX("Channel1.Ascon1.AsconS");