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 FtWriter 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
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Expected output

Writing product data:
====================

Record 1: Widget, Small - $9.99
Record 2: Gadget Pro - $149.95
Record 3: Tool Set - $79.50
Record 4: Premium "Elite" Package - $299.00

Generated CSV:
==============
Product,Quantity,Price,In Stock
"Widget, Small",100,9.99,True
Gadget Pro,50,149.95,True
Tool Set,0,79.50,False
"Premium ""Elite"" Package",25,299.00,True
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Key features demonstrated

• Automatic quoting: Fields containing commas or quotes are automatically quoted
• Quote stuffing: Embedded quotes are duplicated (CSV standard)
• Number formatting: Prices formatted to 2 decimal places
• Type safety: Fields are strongly typed

Code

// 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 {
  FtStringWriter,
  FtWriter,
  FtXmlMetaSerialization,
} from "@pbkware/fielded-text-web";

// Meta as XML
const metaXml = `<?xml version="1.0" encoding="utf-8"?>
<FieldedText>
  <Field Name="PetName" />
  <Field DataType="Float" Name="Age" />
  <Field Name="Color" />
  <Field DataType="DateTime" Name="DateReceived" Format="d MMM yyyy" />
  <Field DataType="Decimal" Name="Price" />
  <Field DataType="Boolean" Name="NeedsWalking" />
  <Field Name="Type" />
</FieldedText>
`;

// 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
const meta = FtXmlMetaSerialization.deserialize(metaXml);

// Create output file path in temp directory
const output = new FtStringWriter();

// Create writer - single class instantiation!
const writer = new FtWriter(meta, output);

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

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