Avoid Link between same two ports.

[snehabihani]

How to avoid link between 2 ports which already drawn.
Means there is link between A to B . so we want to avoid link between A to B, But User can draw a link from A to C and C to B.

[zHaytam]

Hello, is this in version 2.1.6 or the beta 3.0.0?

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On Fri, Sep 9, 2022, 06:40 sneha bihani ***@***.***> wrote: How to avoid link between 2 ports which already drawn. Means there is link between A to B . so we want to avoid link between A to B, But User can draw a link from A to C and C to B — Reply to this email directly, view it on GitHub <#233>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AIFCCVDY4JJNLOBIKIGMJILV5LEWFANCNFSM6AAAAAAQILLWSE> . You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>

[snehabihani]

I am using beta 3.0.0

[snehabihani]

Can you please help?

[zHaytam]

You need to add a custom port and override CanAttachTo like this:

public override bool CanAttachTo(ILinkable other)
{
    if (other is not PortModel otherPort) // Only Port to Port links
        return false;

    if (otherPort == this) // Not the same port
        return false;

    if (otherPort.Locked)
        return false;

    foreach (var link in Links)
    {
        if (link.Target == null) // Ignore ongoing link
            continue;
        
        // Assuming you only do Port to Port links
        var sp = (link.Source as SinglePortAnchor)!.Port;
        var tp = (link.Target as SinglePortAnchor)!.Port;
        // If the link goes to/from this port and the other port
        if ((sp == this && tp == otherPort)
            || (tp == this && sp == otherPort))
        {
            return false;
        }
    }

    return true;
}

[snehabihani]

Thank a lot. It is working as expected.