Class HexStringHelper

Provides utility methods for normalizing and converting variable-length hex-encoded string fields used throughout the XRP Ledger protocol. Fields such as CredentialType, URI, and DIDDocument are stored on-chain as hex-encoded binary blobs. This helper converts between human-readable text and the canonical hex representation.

Inheritance

object

HexStringHelper

Namespace: Xrpl.Models.Utils

Assembly: Xrpl.dll

Syntax

public static class HexStringHelper

Methods

FromHex(string, bool)

Decodes a hex-encoded string back to its human-readable UTF-8 representation.

Declaration

public static string FromHex(string hex, bool trimTrailingNulls = true)

Parameters

Type	Name	Description
string	hex	Hex-encoded string.
bool	trimTrailingNulls	When true (default), decoding stops at the first 0x00 byte — the right behavior for zero-padded fixed-size fields (WalletLocator, currency codes). Pass false for variable-length fields (Memos, metadata) whose bytes must round-trip exactly.

Returns

Type	Description
string	Decoded UTF-8 string, or null if input is null/empty.

IsValidHex(string)

Checks if a string contains only valid hexadecimal characters and has an even length (complete byte pairs).

Declaration

public static bool IsValidHex(string value)

Parameters

Type	Name	Description
string	value

Returns

Type	Description
bool

NormalizeToHex(string, int, string, int)

Normalizes a value for a hex-encoded VL field. If the value is already valid hex, it is uppercased and returned as-is. Otherwise, the value is treated as UTF-8 text and encoded to hex.

Declaration

public static string NormalizeToHex(string value, int maxBytes = 0, string fieldName = null, int padToBytes = 0)

Parameters

Type	Name	Description
string	value	Raw value (hex string or plain text).
int	maxBytes	Maximum allowed byte length (e.g. 64 for CredentialType).
string	fieldName	Field name for error messages.
int	padToBytes	If greater than zero, the result is right-padded with zero bytes to exactly this size. Use for fixed-length fields such as UInt256 / Hash256 (32 bytes). Defaults to 0 (no padding).

Returns

Type	Description
string	Uppercased hex string, or null if input is null/empty.