Call Flow Designer

[Filatura]

Hello everyone, I would like to create a call flow rule that automatically distinguishes whether the caller is a known number (present in the contacts) – if yes, perform one action; if not, perform another. I haven't found a specific guide; using tools like GPT/Grok etc., they propose solutions that use "Execute C# Code," but I can't apply the suggested implementations. Has anyone already developed a similar script? Thanks.


The standard approach uses an "Execute C# Code" component first to query the phonebook, setting a boolean variable like contactFound, followed by a "Create a Condition" checking session.contactFound == true for routing (e.g., known callers to IVR 800, unknown to extension 106).

Working C# Script Example​

Paste this into your "Execute C# Code" component's code editor (pass session.ani as parameter "callerNumber"):


text
<span><span>var tenant = PhoneSystem.Root.GetTenant();<br></span></span><span>var phoneBookEntries = tenant.FindContacts(callerNumber);<br></span><span>contactFound = phoneBookEntries.Count() &gt; 0;<br></span><span></span>
This searches the 3CX company phonebook; if matches exist, sets contactFound to true.

Step-by-Step CFD Setup​

• Drag "Execute C# Code" to the canvas; set input parameter callerNumber = {ANI} and output contactFound (boolean).
• Add "Create a Condition" below; click Fx button, select session.contactFound == true (use Fx to avoid "invalid expression" errors).
• True branch (known): "Transfer Call To" → select IVR or extension (e.g., "800").
• False branch (unknown): "Transfer Call To" → extension (e.g., "106").
• Build → ZIP → Upload to 3CX Admin Console > Advanced > Call Flow Apps; assign to Inbound Rule DID.

Test with known/unknown numbers; if errors persist (e.g., compilation), share your 3CX version or exact code screenshot for tweaks. Many users have succeeded with this phonebook lookup pattern

 

[edossantos_sipcaller]

You're actually posting the solution to your question. Did you try following those steps?

 

[Evolute IT]

You're actually posting the solution to your question. Did you try following those steps?

Sounds like AI slop

 

[fxbastler]

@Filatura
Based on your fragment - better, works, is readable and copy + paste works also:

var tenant = PhoneSystem.Root.GetTenant();
var phoneBookEntries = tenant.FindContacts(callerNumber);
bool contactFound = phoneBookEntries.Count() > 0;
return contactFound;

But the code is bad and I don't know if it's that what you really want.

 

[Filatura]

I'm not very familiar with this tool and I'm struggling to understand how to put together something so simple; I also don't understand the condition part and how to make the true/false distinction.

 

[fxbastler]

I'm not very familiar with this tool and I'm struggling to understand how to put together something so simple; I also don't understand the condition part

that's bad
Read the doc and use the CFD integrated help:
https://www.3cx.com/docs/manual/call-flow-designer/
Expression Editor:
https://www.3cx.com/docs/manual/cfd-prompts-expressions/#h.v17ic2wxant9

how to make the true/false distinction

possible solution:

EQUAL(FindPhonebookContact.ReturnValue,true)

 

[KyriacosS_3CX]

What are the actions to be taken? With update 8 the AI receptionists has knowledge of the phonebook and can transfer calls accordingly, as an option.

 

[Filatura]

Hi , thanks whit yours suggestions i was able to get it working correctly

Yes, AI can do it but OpenAi API key is required.