PromptToExpressionExtension Class
An AI-powered extension that converts natural language into a valid DevExpress filter or expression.
Namespace: DevExpress.AIIntegration.Extensions
Assembly: DevExpress.AIIntegration.v25.2.dll
NuGet Package: DevExpress.AIIntegration
Declaration
public class PromptToExpressionExtension :
PromptToExpressionExtensionBase<PromptToExpressionRequest>Remarks
The PromptToExpressionExtension class converts natural-language input into valid DevExpress expressions. It allows users to describe filtering or calculation logic in plain text and receive a syntactically correct expression that can be applied to filters, calculated fields, or unbound columns.
The extension sends a PromptToExpressionRequest to the registered AI service and returns an expression that conforms to the DevExpress expression language.
The AI service analyzes:
- The user prompt
- The current expression
- Available columns
- Supported functions, parameters, and constants
The following code snippet registers an Azure OpenAI client to use the AI-powered Prompt to Expression extension in a .NET Console application to generate a valid filter expression:
using Azure.AI.OpenAI;
using DevExpress.AIIntegration;
using DevExpress.AIIntegration.Extensions;
using Microsoft.Extensions.AI;
// Register an Azure OpenAI client.
AIExtensionsContainerDefault defaultAIExtensionsContainer = RegisterAzureOpenAIClient(
Environment.GetEnvironmentVariable("AZURE_OPENAI_ENDPOINT"),
Environment.GetEnvironmentVariable("AZURE_OPENAI_APIKEY")
);
// PromptToExpressionAsync converts a human-readable request into
// a machine-readable expression based on the available columns and functions.
var response = await defaultAIExtensionsContainer.PromptToExpressionAsync(
new PromptToExpressionRequest(
"Display orders from the last month where the total amount is greater than $500.", // The user's instruction written in natural language.
string.Empty,
new List<PromptToExpressionRequestBase.ColumnInfo>(){ // Describes data fields that the AI is allowed
new PromptToExpressionRequestBase.ColumnInfo(){ ColumnName = "OrderID" }, // to reference in the generated expression.
new PromptToExpressionRequestBase.ColumnInfo(){ ColumnName = "Price" },
new PromptToExpressionRequestBase.ColumnInfo(){ ColumnName = "OrderDate"}
},
null) // (optional) Specifies custom or supported functions
// that the AI can use when building expressions.
);
Console.WriteLine("Generated Expression: " + response);
// Expected output (the actual output may vary):
// Generated Expression: [OrderDate] >= DateTime.Now.AddMonths(-1) && [Price] > 500
AIExtensionsContainerDefault RegisterAzureOpenAIClient(string azureOpenAIEndpoint, string azureOpenAIKey) {
IChatClient client = new AzureOpenAIClient(new Uri(azureOpenAIEndpoint),
new System.ClientModel.ApiKeyCredential(azureOpenAIKey)).GetChatClient("gpt-4o-mini").AsIChatClient();
return AIExtensionsContainerConsole.CreateDefaultAIExtensionContainer(client);
}
void SetEnvironmentVariables() {
Environment.SetEnvironmentVariable("AZURE_OPENAI_ENDPOINT", {SPECIFY_YOUR_AZURE_ENDPOINT});
Environment.SetEnvironmentVariable("AZURE_OPENAI_APIKEY", {SPECIFY_YOU_AZURE_KEY});
}