C#

Referencing a Pre-Uploaded File by file_id in an AI Request

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Some AI proviers have a Files API that lets you upload content once and then reference it later in generation requests using a file_id. This is especially useful for large documents, reuse across multiple prompts, or keeping inputs structured and separate from your prompt text.

This example demonstrates how to use a file_id in a request.

C#

bool success = false;

success = false;

// This example assumes the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

Chilkat.Ai ai = new Chilkat.Ai();

// The provider can be "openai", "google", "claude", "mistral", "deepseek", "xai", or any provider
// that supports referencing pre-uploaded files by a file_id (or file uri).
ai.Provider = "openai";

// Use your provider's API key.
ai.ApiKey = "MY_API_KEY";

// Choose a model.
ai.Model = "gpt-5-mini";

// See the following example showing how to upload a file
// Upload a File to an AI Provider (OpenAI, Google, Antropic, X)

// Use the file_id of the pre-uploaded file.
string file_id = "file-5G2xncrEiHbVfYPRpFgP9c";
ai.InputAddFileId(file_id,"application/json");

ai.InputAddText("Explain why Hamlet delays taking revenge, using only evidence from the file.");

// Ask the AI for text output.
success = ai.Ask("text");
if (success == false) {
    Debug.WriteLine(ai.LastErrorText);
    return;
}

// Get the text response.
Chilkat.StringBuilder sbResponse = new Chilkat.StringBuilder();
ai.GetOutputTextSb(sbResponse);
Debug.WriteLine(sbResponse.GetAsString());