hexToInt method

int? hexToInt()

Converts a hexadecimal string to an integer (int).

This method attempts to parse the string as a hexadecimal number. It performs several checks to ensure the input is a valid hexadecimal string and that the resulting value can be represented as an int (signed 64-bit).

The method correctly handles both uppercase and lowercase hex strings, normalizing to uppercase for the overflow comparison.

Returns: An int representation of the hexadecimal string, or null if:

• The string is empty
• The string contains non-hexadecimal characters
• The value exceeds the maximum signed 64-bit integer (0x7FFFFFFFFFFFFFFF)

Prints a warning to the debug console if the input is invalid or too large.

Example:

'FF'.hexToInt(); // Returns 255
'ff'.hexToInt(); // Returns 255 (case-insensitive)
'1A3F'.hexToInt(); // Returns 6719
'7fffffffffffffff'.hexToInt(); // Returns 9223372036854775807 (max int64)
''.hexToInt(); // Returns null
'invalid-hex'.hexToInt(); // Returns null, prints a warning
'8000000000000000'.hexToInt(); // Returns null, prints a warning (too large)

Implementation

int? hexToInt() {
  if (isEmpty) {
    return null;
  }

  // Check if the hexadecimal string is valid using a regular expression.
  if (!_hexRegex.hasMatch(this)) {
    return null;
  }

  // Check if the hexadecimal string is too large to be represented as an int.
  // Normalize to uppercase for consistent comparison since the input can be
  // mixed case (e.g., '7fffffffffffffff' should equal '7FFFFFFFFFFFFFFF').
  final String upperHex = toUpperCase();
  if (length > 16 || (length == 16 && upperHex.compareTo(_maxInt64Hex) > 0)) {
    return null;
  }

  // Convert the hexadecimal string to an int and return it.
  return int.parse(this, radix: 16);
}