Core Parsing

/**
 * Creates a new CSV to JSON converter with optional configuration
 * @param param - Optional parsing parameters to customize CSV parsing behavior
 * @param options - Optional Node.js Transform stream options
 * @returns Converter instance for chaining parsing operations
 */
function csvtojson(
  param?: Partial<CSVParseParam>, 
  options?: TransformOptions
): Converter;

import csvtojson from "csvtojson";

// Default parsing
const converter = csvtojson();

// Custom delimiter
const converter = csvtojson({ delimiter: ";" });

// Multiple options
const converter = csvtojson({
  delimiter: ",",
  trim: true,
  noheader: false,
  checkType: true
});

/**
 * Alias to the main csvtojson factory function
 */
csvtojson.csv: typeof csvtojson;

/**
 * Direct access to the Converter class for advanced usage
 */
csvtojson.Converter: typeof Converter;

import csvtojson from "csvtojson";

// Using csv alias
const converter1 = csvtojson.csv({ delimiter: ";" });

// Direct Converter class usage
const converter2 = new csvtojson.Converter({ trim: true });

interface CSVParseParam {
  /** 
   * Delimiter used for separating columns. Use "auto" for auto-detection,
   * or provide array of potential delimiters like [",","|","$"]
   * @default ","
   */
  delimiter: string | string[];
  
  /** 
   * Quote character for surrounding column content containing delimiters.
   * Set to "off" to ignore all quotes
   * @default '"'
   */
  quote: string;
  
  /** 
   * Trim spaces surrounding column content
   * @default true
   */
  trim: boolean;
  
  /** 
   * Indicates CSV data has no header row and first row is data
   * @default false
   */
  noheader: boolean;
  
  /** 
   * Array to specify headers of CSV data. Overrides CSV header row if noheader is false
   * @default undefined
   */
  headers?: string[];
  
  /** 
   * Output format: "json" for JSON objects, "csv" for array format, "line" for raw lines
   * @default "json"
   */
  output: "json" | "csv" | "line";
}

// Auto-detect delimiter
const converter = csvtojson({ 
  delimiter: "auto" 
});

// Multiple potential delimiters
const converter = csvtojson({ 
  delimiter: [",", ";", "|", "\t"] 
});

// Custom headers for headerless CSV
const converter = csvtojson({
  noheader: true,
  headers: ["id", "name", "email", "age"]
});

// Different output formats
const csvArray = await csvtojson({ output: "csv" })
  .fromString("1,2,3\n4,5,6");
// Result: [["1","2","3"], ["4","5","6"]]

const lineArray = await csvtojson({ output: "line" })
  .fromString("1,2,3\n4,5,6");
// Result: ["1,2,3", "4,5,6"]

interface CSVParseParam {
  /** 
   * Turn on field type checking and conversion
   * @default false
   */
  checkType: boolean;
  
  /** 
   * Convert string "null" to null object in JSON outputs
   * @default false
   */
  nullObject: boolean;
  
  /** 
   * Ignore empty values in CSV columns
   * @default false
   */
  ignoreEmpty: boolean;
}

// Enable type detection
const converter = csvtojson({
  checkType: true,
  nullObject: true
});

const result = await converter.fromString('name,age,active\nAlice,25,true\nBob,null,false');
// Result: [
//   { name: "Alice", age: 25, active: true },
//   { name: "Bob", age: null, active: false }
// ]

interface CSVParseParam {
  /** 
   * Maximum character count a CSV row can have. 0 means infinite.
   * Prevents memory issues with corrupted data
   * @default 0
   */
  maxRowLength: number;
  
  /** 
   * Check if column count matches header count
   * @default false
   */
  checkColumn: boolean;
  
  /** 
   * Always interpret each line as a row, preventing inline line breaks
   * @default false
   */
  alwaysSplitAtEOL: boolean;
}

// Limit row length for safety
const converter = csvtojson({
  maxRowLength: 65535,
  checkColumn: true
});