PowerApps中Chatbot连接报错求助：GenerateAnswer参数数量无效

Hey there, let's tackle that frustrating "Invalid number of arguments" error you're hitting when triggering the button's OnSelect event. The root issue is a mismatch in how you're calling the QnA Maker connector's GenerateAnswer function—let's break this down step by step.

First, Let's Recap Your Setup #

Your screen OnStart code looks solid for initializing the chat:

ClearCollect(chat,{id:0,name:"EmployeeFaqBot",text:"Welcome " &User().FullName &" ! Enter your Query"})

The problem lies in how you're invoking OPMS_Service.GenerateAnswer in your button code.

Why Your Original Code Fails #

Your initial button OnSelect code includes an extra, unnecessary parameter:

Collect(chat,{id:1,name:User().FullName,text:TextInput1.Text}); 
Collect(chat,{id:0,name:"EmployeeFaqBot",text:First(OPMS_Service.GenerateAnswer("a6*****7c","application/json",{question:TextInput1.Text}).answers).answer})

The QnA Maker connector's GenerateAnswer function only expects two required parameters:

1. Your QnA Knowledge Base ID (the "a6*****7c" value you already have)
2. A request object containing the question key

The "application/json" string you added is redundant—PowerApps handles the content type automatically for the connector, so passing it here causes the "invalid number of arguments" error.

The Corrected Button OnSelect Code #

Replace your button code with this version, which removes the extra parameter and follows the correct function structure:

Collect(chat, {id: 1, name: User().FullName, text: TextInput1.Text});
Collect(chat, {id: 0, name: "EmployeeFaqBot", text: First(OPMS_Service.GenerateAnswer("a6*****7c", {question: TextInput1.Text}).answers).answer})

What Was Wrong With Your Other Attempts #

Let's quickly go over why your alternate code snippets didn't work:

• Attempt 1 (missing Knowledge Base ID): GenerateAnswer({question:TextInput1.Text}) omits the first required parameter (your KB ID), so the function doesn't know which QnA dataset to query.
• Attempt 2 (swapped parameters): GenerateAnswer("application/json",{question:TextInput1.Text}) uses the content type string as the KB ID, which is an invalid value and mismatches the expected parameter type.
• Attempt 3 (invalid object syntax): GenerateAnswer({"application/json",question:TextInput1.Text}) uses broken object syntax (you can't list values without keys) plus still includes the unnecessary content type.

Bonus: Add Robust Error Handling #

To make your chat more user-friendly, wrap the bot response in an IfError block to handle cases where the QnA service might fail:

Collect(chat, {id: 1, name: User().FullName, text: TextInput1.Text});
IfError(
    Collect(chat, {id: 0, name: "EmployeeFaqBot", text: First(OPMS_Service.GenerateAnswer("a6*****7c", {question: TextInput1.Text}).answers).answer}),
    Collect(chat, {id: 0, name: "EmployeeFaqBot", text: "Sorry, I couldn't process your query right now. Please try again later."})
)

内容的提问来源于stack exchange，提问作者Jyoti Sharma