TPDFlibLogger

Data types, document management

Description

TPDFlibLogger is the structured logger class attached to a TPDFlib instance through its Logger property. When assigned, it receives Debug, Info, Warn and Error records, each carrying a numeric code drawn from the existing LastErrorCode taxonomy and a human-readable message

The logger is caller-owned and may be shared across several TPDFlib instances. It is nil by default, so the no-logger path is zero-cost

Syntax

Delphi

TPDFlibLogger = Class
  Public
    Constructor Create; Virtual;
    Destructor Destroy; Override;
    Procedure Log(Level: TPDFlibLogLevel; Code: Integer; Const Msg: WideString); Overload;
    Procedure Log(Level: TPDFlibLogLevel; Code: Integer; Const Msg: WideString;
      Const ExtraFieldsText: WideString); Overload;
    Procedure Debug(Code: Integer; Const Msg: WideString);
    Procedure Info(Code: Integer; Const Msg: WideString);
    Procedure Warn(Code: Integer; Const Msg: WideString);
    Procedure Error_(Code: Integer; Const Msg: WideString);
    Property Level: TPDFlibLogLevel Read FLevel Write FLevel;
    Property OnLog: TPDFlibLogEvent Read FOnLog Write FOnLog;
    Property FileName: WideString Read FFileName Write SetFileName;
  End;

Properties

Level	The minimum severity to emit; records below this threshold are silently dropped
OnLog	A host callback invoked for every emitted record, receiving the level, code and message
FileName	When set, records are also written to this file through a thread-safe `TStreamWriter` sink; clear it to stop file logging

Remarks

The convenience methods Debug, Info, Warn and Error_ call Log with the matching level

File writes are serialized with a critical section, so a single logger instance is safe to use from worker threads