Basic Write Example

This example demonstrates how to write CSV data using the FieldedText library.

What it does

1. Creates metadata for a product inventory CSV file
2. Defines fields for Product name, Quantity, Price, and In Stock status
3. Uses SerializationWriter to generate CSV output
4. Writes multiple product records
5. Handles special characters (commas, quotes) automatically

Running the example

npx tsx examples/basic-write/index.ts
Copy

// Basic Write Example
// Demonstrates writing CSV data using the FieldedText library
// This example matches the C# BasicWrite example - it loads meta from BasicExampleMeta.ftm

import {
  FtNodeFileWriter,
  FtNodeXmlMetaSerialization,
} from "@pbkware/fielded-text-node";
import * as fs from "node:fs";
import * as os from "node:os";
import * as path from "node:path";
import { fileURLToPath } from "node:url";

// Get directory path for ESM module
const __filename = fileURLToPath(import.meta.url);
const __dirname = path.dirname(__filename);

// Name of file containing Meta
const metaFileName = "meta.ftm";
// Name of file to be written
const csvFileName = "node-basic-example.csv";

// Define FieldNames
const PetNameFieldName = "PetName";
const AgeFieldName = "Age";
const ColorFieldName = "Color";
const DateReceivedFieldName = "DateReceived";
const PriceFieldName = "Price";
const NeedsWalkingFieldName = "NeedsWalking";
const TypeFieldName = "Type";

// Load meta from file
const metaFilePath = path.join(__dirname, metaFileName);
const meta = FtNodeXmlMetaSerialization.deserializeFromFile(metaFilePath);

// Create output file path in temp directory
const tmpDir = os.tmpdir();
const fieldedTextTmpDir = path.join(tmpDir, "fielded-text/examples");
const outputPath = path.join(fieldedTextTmpDir, csvFileName);

// Ensure the directory exists
fs.mkdirSync(fieldedTextTmpDir, { recursive: true });

// Create writer - single class instantiation!
using writer = new FtNodeFileWriter(outputPath, meta);

console.log("Writing pet data:");
console.log("=================\n");

// Write 1st Record
writer.setFieldValueByName(PetNameFieldName, "Rover");
writer.setFieldValueByName(AgeFieldName, 4.5);
writer.setFieldValueByName(ColorFieldName, "Brown");
writer.setFieldValueByName(DateReceivedFieldName, new Date(2004, 1, 12)); // Feb 12, 2004
writer.setFieldValueByName(PriceFieldName, 80);
writer.setFieldValueByName(NeedsWalkingFieldName, true);
writer.setFieldValueByName(TypeFieldName, "Dog");
writer.write();
console.log("Record 1: Rover (Dog)");

// Write 2nd Record
writer.setFieldValueByName(PetNameFieldName, "Charlie");
writer.setFieldValueByName(AgeFieldName, null);
writer.setFieldValueByName(ColorFieldName, "Gold");
writer.setFieldValueByName(DateReceivedFieldName, new Date(2007, 3, 5)); // Apr 5, 2007
writer.setFieldValueByName(PriceFieldName, 12.3);
writer.setFieldValueByName(NeedsWalkingFieldName, false);
writer.setFieldValueByName(TypeFieldName, "Fish");
writer.write();
console.log("Record 2: Charlie (Fish)");

// Read and display the generated CSV
const csvContent = fs.readFileSync(outputPath, "utf-8");

console.log("\nGenerated CSV:");
console.log("==============");
console.log(csvContent);

console.log(`\nOutput written to: ${outputPath}`);
Copy