TChilkatJsonObject Delphi ActiveX Reference Documentation

TChilkatJsonObject

Represents a JSON object, which contains an unordered set of name/value pairs. Each value can be a string, number, JSON object, JSON array, true, false, or null.

Importing the Chilkat ActiveX into Delphi

Important: Whenever upgrading to a new version of Chilkat, make sure to re-imported ActiveX DLL into Delphi to regenerate the files described below.

Two things are required to use an ActiveX in Delphi:

  1. The ActiveX DLL needs to be registered via regsvr32 on the system where the Delphi application runs. See How To Register ActiveX DLLs for detailed information.
  2. The ActiveX component needs to be "imported". Use the Delphi Import Component Wizard to import the Chilkat type library. This creates the following files: Chilkat_v9_5_0_TLB.pas and Chilkat_v9_5_0_TLB.dcr. The Chilkat_v9_5_0_TLB.pas should be added to your project.

To import the Chilkat type library, do the following:

  1. In the Delphi RAD Studio, select the menu item "Component" --> "Import a Type Library".
  2. Find "Chilkat ActiveX v9.5.0" in the list and select it. This will only appear in the list if the ChilkatAx-9.5.0-win32.dll (or ChilkatAx-9.5.0-x64.dll) has been registered w/ regsvr32.
  3. Check the "Generate Component Wrappers" checkbox.
  4. Select a directory where the unit files (.pas and .dcr) will be generated.
  5. Select "Create Unit" and then "Finish".
  6. Add the .pas to your Delphi project.

To use a Chilkat ActiveX object in your Delphi code, add "Chilkat_v9_5_0_TLB" to the "uses" statement. For example:

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
  Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Chilkat_v9_5_0_TLB;

Object Creation

var
obj: TChilkatJsonObject;
...
begin
obj := TChilkatJsonObject.Create(Self);
...
// When finished, free the object instance.
obj.Free();

Properties

property DebugLogFilePath: WideString

If set to a file path, causes each Chilkat method or property call to automatically append it's LastErrorText to the specified log file. The information is appended such that if a hang or crash occurs, it is possible to see the context in which the problem occurred, as well as a history of all Chilkat calls up to the point of the problem. The VerboseLogging property can be set to provide more detailed information.

This property is typically used for debugging the rare cases where a Chilkat method call hangs or generates an exception that halts program execution (i.e. crashes). A hang or crash should generally never happen. The typical causes of a hang are:

  1. a timeout related property was set to 0 to explicitly indicate that an infinite timeout is desired,
  2. the hang is actually a hang within an event callback (i.e. it is a hang within the application code), or
  3. there is an internal problem (bug) in the Chilkat code that causes the hang.

property DelimiterChar: WideString

Introduced in version 9.5.0.58

Sets the delimiter char for JSON paths. The default value is ".". To use Firebase style paths, set this property to "/". (This is a string property that should have a length of 1 char.)

property EmitCompact: Integer

Introduced in version 9.5.0.56

If 1 then the Emit method outputs in the most compact form possible (a single-line with no extra whitespace). If 0, then emits with whitespace and indentation to make the JSON human-readable.

The default value is 1.

property EmitCrLf: Integer

Introduced in version 9.5.0.56

If 1 then the Emit method uses CRLF line-endings when emitting the non-compact (pretty-print) format. If 0, then bare-LF's are emitted. (The compact format emits to a single line with no end-of-line characters.) Windows systems traditionally use CRLF line-endings, whereas Linux, Mac OS X, and other systems traditionally use bare-LF line-endings.

The default value is 1.

property I: Integer

Introduced in version 9.5.0.56

The value of the "i" index to be used when evaluating a JSON path.

JSON Paths

property J: Integer

Introduced in version 9.5.0.56

The value of the "j" index to be used when evaluating a JSON path.

property K: Integer

Introduced in version 9.5.0.56

The value of the "k" index to be used when evaluating a JSON path.

property LastBinaryResult: OleVariant readonly

Introduced in version 9.5.0.52

The binary data returned by the last (binary data returning) method called. Only available if Chilkat.Global.KeepBinaryResult is set to 1. This provides a means for obtaining large varbinary results in the SQL Server environment (where limitations exist in getting large amounts of data returned by method calls, but where temp tables can be used for binary properties).

property LastErrorHtml: WideString readonly

Provides information in HTML format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.

property LastErrorText: WideString readonly

Provides information in plain-text format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.

Concept of LastErrorText

LastErrorText Standard Information

property LastErrorXml: WideString readonly

Provides information in XML format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.

property LastMethodSuccess: Integer

Introduced in version 9.5.0.52

Indicate whether the last method call succeeded or failed. A value of 1 indicates success, a value of 0 indicates failure. This property is automatically set for method calls. It is not modified by property accesses. The property is automatically set to indicate success for the following types of method calls:

  • Any method that returns a string.
  • Any method returning a Chilkat object, binary bytes, or a date/time.
  • Any method returning a standard boolean status value where success = 1 and failure = 0.
  • Any method returning an integer where failure is defined by a return value less than zero.

Note: Methods that do not fit the above requirements will always set this property equal to 1. For example, a method that returns no value (such as a "void" in C++) will technically always succeed.

property LastStringResult: WideString readonly

Introduced in version 9.5.0.52

The string return value of the last (string returning) method called. Only available if Chilkat.Global.KeepStringResult is set to 1. This provides a means for obtaining large string results in the SQL Server environment (where limitations exist in getting long strings returned by method calls, but where temp tables can be used for string properties).

Long Strings Returned by ActiveX Methods in SQL Server

property LastStringResultLen: Integer readonly

Introduced in version 9.5.0.53

The length, in characters, of the string contained in the LastStringResult property.

property Size: Integer readonly

Introduced in version 9.5.0.56

The number of name/value members in this JSON object.

JSON Iterate Members

property VerboseLogging: Integer

If set to 1, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. The default value is 0. Verbose logging should only be used for debugging. The potentially large quantity of logged information may adversely affect peformance.

property Version: WideString readonly

Version of the component/library, such as "9.5.0.63"

Methods

function AddArrayAt(index: Integer; name: WideString): Integer;

Introduced in version 9.5.0.56

Inserts a new and empty JSON array member to the position indicated by index. To prepend, pass an index of 0. To append, pass an index of -1. Indexing is 0-based (the 1st member is at index 0).

Returns 1 for success, 0 for failure.

Create more Complex JSON Document

function AddBoolAt(index: Integer; name: WideString; value: Integer): Integer;

Introduced in version 9.5.0.56

Inserts a new boolean member to the position indicated by index. To prepend, pass an index of 0. To append, pass an index of -1. Indexing is 0-based (the 1st member is at index 0).

Returns 1 for success, 0 for failure.

JSON: Miscellaneous Operations

function AddIntAt(index: Integer; name: WideString; value: Integer): Integer;

Introduced in version 9.5.0.56

Inserts a new integer member to the position indicated by index. To prepend, pass an index of 0. To append, pass an index of -1. Indexing is 0-based (the 1st member is at index 0).

Returns 1 for success, 0 for failure.

Create JSON Document

function AddNullAt(index: Integer; name: WideString): Integer;

Introduced in version 9.5.0.56

Inserts a new null member to the position indicated by index. To prepend, pass an index of 0. To append, pass an index of -1. Indexing is 0-based (the 1st member is at index 0).

Returns 1 for success, 0 for failure.

JSON: Miscellaneous Operations

function AddNumberAt(index: Integer; name: WideString; numericStr: WideString): Integer;

Introduced in version 9.5.0.56

Inserts a new numeric member to the position indicated by index. The numericStr is an integer, float, or double already converted to a string in the format desired by the application. To prepend, pass an index of 0. To append, pass an index of -1. Indexing is 0-based (the 1st member is at index 0).

Returns 1 for success, 0 for failure.

Create more Complex JSON Document

function AddObjectAt(index: Integer; name: WideString): Integer;

Introduced in version 9.5.0.56

Inserts a new and empty JSON object member to the position indicated by index. To prepend, pass an index of 0. To append, pass an index of -1. Indexing is 0-based (the 1st member is at index 0).

Returns 1 for success, 0 for failure.

Create more Complex JSON Document

function AddStringAt(index: Integer; name: WideString; value: WideString): Integer;

Introduced in version 9.5.0.56

Inserts a new string member to the position indicated by index. To prepend, pass an index of 0. To append, pass an index of -1. Indexing is 0-based (the 1st member is at index 0).

Returns 1 for success, 0 for failure.

Create JSON Document

function AppendArray(name: WideString): TChilkatJsonArray;

Introduced in version 9.5.0.58

Appends a new and empty JSON array and returns it.

Returns nil on failure

function AppendBool(name: WideString; value: Integer): Integer;

Introduced in version 9.5.0.58

Appends a new boolean member. (This is the same as passing -1 to the AddBoolAt method.)

Returns 1 for success, 0 for failure.

function AppendInt(name: WideString; value: Integer): Integer;

Introduced in version 9.5.0.58

Appends a new integer member. (This is the same as passing an index of -1 to the AddIntAt method.)

Returns 1 for success, 0 for failure.

function AppendObject(name: WideString): TChilkatJsonObject;

Introduced in version 9.5.0.58

Appends a new and empty JSON object and returns it.

Returns nil on failure

function AppendString(name: WideString; value: WideString): Integer;

Introduced in version 9.5.0.58

Appends a new string member. (This is the same as passing -1 to the AddStringAt method.)

Returns 1 for success, 0 for failure.

function AppendStringArray(name: WideString; values: TChilkatStringTable): Integer;

Introduced in version 9.5.0.67

Appends an array of string values.

Returns 1 for success, 0 for failure.

JSON Append String Array

function ArrayAt(index: Integer): TChilkatJsonArray;

Introduced in version 9.5.0.56

Returns the JSON array that is the value of the Nth member. Indexing is 0-based (the 1st member is at index 0).

Returns nil on failure

Create more Complex JSON Document

function ArrayOf(jsonPath: WideString): TChilkatJsonArray;

Introduced in version 9.5.0.56

Returns the JSON array at the specified jsonPath.

Returns nil on failure

JSON: Access Array Values

Modify Parts of JSON Document

JSON Paths

function BoolAt(index: Integer): Integer;

Introduced in version 9.5.0.56

Returns the boolean value of the Nth member. Indexing is 0-based (the 1st member is at index 0).

JSON: Miscellaneous Operations

function BoolOf(jsonPath: WideString): Integer;

Introduced in version 9.5.0.56

Returns the boolean at the specified jsonPath.

JSON: Miscellaneous Operations

JSON Paths

function BytesOf(jsonPath: WideString; encoding: WideString; bd: TChilkatBinData): Integer;

Introduced in version 9.5.0.68

Appends the binary bytes at the specified jsonPath to bd. The encoding indicates the encoding of the bytes, such as "base64", "hex", etc.

Returns 1 for success, 0 for failure.

function Clone(): TChilkatJsonObject;

Introduced in version 9.5.0.66

Returns a copy of this JSON object.

Returns nil on failure

function Delete(name: WideString): Integer;

Introduced in version 9.5.0.56

Deletes the member at having the name specified by name.

Returns 1 for success, 0 for failure.

JSON: Renaming and Deleting Members

function DeleteAt(index: Integer): Integer;

Introduced in version 9.5.0.56

Deletes the member at index index. Indexing is 0-based (the 1st member is at index 0).

Returns 1 for success, 0 for failure.

JSON: Renaming and Deleting Members

function Emit(): WideString;

Introduced in version 9.5.0.56

Writes the JSON document (rooted at the caller) and returns as a string.

Returns a zero-length WideString on failure

Pretty Print JSON (Formatter, Beautifier)

function EmitSb(sb: TChilkatStringBuilder): Integer;

Introduced in version 9.5.0.62

Appends the JSON to a StringBuilder object.

Returns 1 for success, 0 for failure.

function EmitWithSubs(subs: TChilkatHashtable; omitEmpty: Integer): WideString;

Introduced in version 9.5.0.67

Emits the JSON document with variable substitutions applied. If omitEmpty is 1, then members having empty strings or empty arrays are omitted.

Returns a zero-length WideString on failure

Using Pre-defined JSON Templates

function FindObjectWithMember(name: WideString): TChilkatJsonObject;

Introduced in version 9.5.0.67

Recursively searches the JSON subtree rooted at the caller's node for a JSON object containing a member having a specified name. (If the caller is the root node of the entire JSON document, then the entire JSON document is searched.) Returns the first match or nil if not found.

Returns nil on failure

function FindRecord(arrayPath: WideString; relPath: WideString; value: WideString; caseSensitive: Integer): TChilkatJsonObject;

Introduced in version 9.5.0.63

Finds a JSON record in an array where a particular field equals or matches a value pattern. Reviewing the example below is the best way to understand this function.

Returns nil on failure

JSON FindRecord Example

function FindRecordString(arrayPath: WideString; relPath: WideString; value: WideString; caseSensitive: Integer; retRelPath: WideString): WideString;

Introduced in version 9.5.0.63

Finds a JSON value in an record array where a particular field equals or matches a value pattern. Reviewing the example below is the best way to understand this function.

Returns a zero-length WideString on failure

JSON FindRecordString Example

function FirebaseApplyEvent(name: WideString; data: WideString): Integer;

Introduced in version 9.5.0.58

Applies a Firebase event to the JSON. The data contains JSON having a format such as

{"path": "/", "data": {"a": 1, "b": 2}}
The name should be "put" or "patch".

Returns 1 for success, 0 for failure.

Firebase Receive Server-Sent Events (text/event-stream)

function FirebasePatch(jsonPath: WideString; jsonData: WideString): Integer;

Introduced in version 9.5.0.58

For each key in the jsonData, update (or add) the corresponding key in the JSON at the given jsonPath. The jsonPath is relative to this JSON object. (This is effectively applying a Firebase patch event.)

Returns 1 for success, 0 for failure.

Firebase JSON Put and Patch

function FirebasePut(jsonPath: WideString; value: WideString): Integer;

Introduced in version 9.5.0.58

Inserts or replaces the value at the jsonPath. The value can contain JSON text, an integer (in decimal string format), a boolean (true/false), the keyword "null", or a quoted string.

The jsonPath is relative to this JSON object. (This is effectively applying a Firebase put event.)

Returns 1 for success, 0 for failure.

Firebase JSON Put and Patch

function GetDocRoot(): TChilkatJsonObject;

Introduced in version 9.5.0.56

Returns the root of the JSON document. The root can be obtained from any JSON object within the JSON document. The entire JSON document remains in memory as long as at least one JSON object is referenced by the application. When the last reference is removed, the entire JSON document is automatically dellocated.

Returns nil on failure

Get the Root of a JSON Document

function HasMember(jsonPath: WideString): Integer;

Introduced in version 9.5.0.58

Returns 1 if the item at the jsonPath exists.

Returns 1 for success, 0 for failure.

function IndexOf(name: WideString): Integer;

Introduced in version 9.5.0.56

Returns the index of the member having the given name. Returns -1 if the name is not found.

Get the Index of a JSON Member

function IntAt(index: Integer): Integer;

Introduced in version 9.5.0.56

Returns the integer value of the Nth member. Indexing is 0-based (the 1st member is at index 0).

JSON Iterate Members

function IntOf(jsonPath: WideString): Integer;

Introduced in version 9.5.0.56

Returns the integer at the specified jsonPath.

JSON: Miscellaneous Operations

JSON Paths

function IsNullAt(index: Integer): Integer;

Introduced in version 9.5.0.56

Returns the boolean value of the member having the specified index.

JSON: Miscellaneous Operations

function IsNullOf(jsonPath: WideString): Integer;

Introduced in version 9.5.0.56

Returns 1 if the value at the specified jsonPath is null. Otherwise returns 0.

JSON: Miscellaneous Operations

JSON Paths

function Load(json: WideString): Integer;

Introduced in version 9.5.0.56

Parses a JSON string and loads it into this JSON object to provide DOM-style access.

Returns 1 for success, 0 for failure.

Load JSON Data at Path

Load a JSON Array

Loading and Parsing a JSON Array

function LoadFile(path: WideString): Integer;

Introduced in version 9.5.0.56

Loads a JSON file into this JSON object. The path is the file path to the JSON file.

Returns 1 for success, 0 for failure.

Load a JSON Array

function LoadPredefined(name: WideString): Integer;

Introduced in version 9.5.0.67

Loads this JSON object from a predefined document having a specified name.

Returns 1 for success, 0 for failure.

Using Pre-defined JSON Templates

function LoadSb(sb: TChilkatStringBuilder): Integer;

Introduced in version 9.5.0.62

Loads JSON from the contents of a StringBuilder object.

Returns 1 for success, 0 for failure.

function NameAt(index: Integer): WideString;

Introduced in version 9.5.0.56

Returns the name of the Nth member. Indexing is 0-based (the 1st member is at index 0).

Returns a zero-length WideString on failure

JSON Iterate Members

function ObjectAt(index: Integer): TChilkatJsonObject;

Introduced in version 9.5.0.56

Returns the JSON object that is the value of the Nth member. Indexing is 0-based (the 1st member is at index 0).

Returns nil on failure

Create more Complex JSON Document

function ObjectOf(jsonPath: WideString): TChilkatJsonObject;

Introduced in version 9.5.0.56

Returns the JSON object at the specified jsonPath.

Returns nil on failure

JSON: Nested Objects

JSON Paths

function Predefine(name: WideString): Integer;

Introduced in version 9.5.0.67

Adds or replaces this JSON to an internal global set of predefined JSON documents that can be subsequently loaded by name.

Returns 1 for success, 0 for failure.

Using Pre-defined JSON Templates

function Rename(oldName: WideString; newName: WideString): Integer;

Introduced in version 9.5.0.56

Renames the member named oldName to newName.

Returns 1 for success, 0 for failure.

JSON: Renaming and Deleting Members

function RenameAt(index: Integer; name: WideString): Integer;

Introduced in version 9.5.0.56

Renames the member at index to name.

Returns 1 for success, 0 for failure.

JSON: Renaming and Deleting Members

function SetBoolAt(index: Integer; value: Integer): Integer;

Introduced in version 9.5.0.56

Sets the boolean value of the Nth member. Indexing is 0-based (the 1st member is at index 0).

Returns 1 for success, 0 for failure.

Modify Parts of JSON Document

function SetBoolOf(jsonPath: WideString; value: Integer): Integer;

Introduced in version 9.5.0.56

Sets the boolean value at the specified jsonPath.

Returns 1 for success, 0 for failure.

Modify Parts of JSON Document

JSON Paths

function SetIntAt(index: Integer; value: Integer): Integer;

Introduced in version 9.5.0.56

Sets the integer value of the Nth member. Indexing is 0-based (the 1st member is at index 0).

Returns 1 for success, 0 for failure.

Modify Parts of JSON Document

function SetIntOf(jsonPath: WideString; value: Integer): Integer;

Introduced in version 9.5.0.56

Sets the integer at the specified jsonPath.

Returns 1 for success, 0 for failure.

Modify Parts of JSON Document

JSON Paths

function SetNullAt(index: Integer): Integer;

Introduced in version 9.5.0.56

Sets the value of the Nth member to null. Indexing is 0-based (the 1st member is at index 0).

Returns 1 for success, 0 for failure.

JSON: Miscellaneous Operations

function SetNullOf(jsonPath: WideString): Integer;

Introduced in version 9.5.0.56

Sets the value at the specified jsonPath to null.

Returns 1 for success, 0 for failure.

JSON: Miscellaneous Operations

JSON Paths

function SetNumberAt(index: Integer; value: WideString): Integer;

Introduced in version 9.5.0.56

Sets the numeric value of the Nth member. The value is an integer, float, or double already converted to a string in the format desired by the application. Indexing is 0-based (the 1st member is at index 0).

Returns 1 for success, 0 for failure.

JSON: Miscellaneous Operations

function SetNumberOf(jsonPath: WideString; value: WideString): Integer;

Introduced in version 9.5.0.56

Sets the numeric value at the specified jsonPath. The value is an integer, float, or double already converted to a string in the format desired by the application.

Returns 1 for success, 0 for failure.

JSON: Miscellaneous Operations

JSON Paths

function SetStringAt(index: Integer; value: WideString): Integer;

Introduced in version 9.5.0.56

Sets the string value of the Nth member. Indexing is 0-based (the 1st member is at index 0).

Returns 1 for success, 0 for failure.

Modify Parts of JSON Document

function SetStringOf(jsonPath: WideString; value: WideString): Integer;

Introduced in version 9.5.0.56

Sets the string value at the specified jsonPath.

Returns 1 for success, 0 for failure.

Modify Parts of JSON Document

JSON Paths

function SizeOfArray(jsonPath: WideString): Integer;

Introduced in version 9.5.0.56

Returns the size of the array at the given jsonPath. Returns -1 if the jsonPath does not evaluate to an existent JSON array.

JSON Paths

function StringAt(index: Integer): WideString;

Introduced in version 9.5.0.56

Returns the string value of the Nth member. Indexing is 0-based (the 1st member is at index 0).

Returns a zero-length WideString on failure

JSON Iterate Members

function StringOf(jsonPath: WideString): WideString;

Introduced in version 9.5.0.56

Returns the string value at the specified jsonPath.

Returns a zero-length WideString on failure

JSON: Miscellaneous Operations

JSON Paths

JSON Paths that need Double Quotes

function StringOfSb(jsonPath: WideString; sb: TChilkatStringBuilder): Integer;

Introduced in version 9.5.0.68

Appends the string value at the specified jsonPath to sb.

Returns 1 for success, 0 for failure.

function TypeAt(index: Integer): Integer;

Introduced in version 9.5.0.58

Returns the type of data at the given index. Possible return values are:

  1. string
  2. number
  3. object
  4. array
  5. boolean
  6. null
Returns -1 if no member exists at the given index.

function UpdateBd(jsonPath: WideString; encoding: WideString; bd: TChilkatBinData): Integer;

Introduced in version 9.5.0.68

Updates or appends a new string member with the encoded contents of bd. If the full path specified by jsonPath does not exist, it is automatically created as needed. The bytes contained in bd are encoded according to encoding (such as "base64", "hex", etc.)

Returns 1 for success, 0 for failure.

function UpdateBool(jsonPath: WideString; value: Integer): Integer;

Introduced in version 9.5.0.63

Updates or appends a new boolean member. If the full path specified by jsonPath does not exist, it is automatically created as needed.

Returns 1 for success, 0 for failure.

function UpdateInt(jsonPath: WideString; value: Integer): Integer;

Introduced in version 9.5.0.63

Updates or appends a new integer member. If the full path specified by jsonPath does not exist, it is automatically created as needed.

Returns 1 for success, 0 for failure.

function UpdateNull(jsonPath: WideString): Integer;

Introduced in version 9.5.0.65

Updates or appends a null member. If the full path specified by jsonPath does not exist, it is automatically created as needed.

Returns 1 for success, 0 for failure.

function UpdateNumber(jsonPath: WideString; numericStr: WideString): Integer;

Introduced in version 9.5.0.65

Updates or appends a new numeric member. If the full path specified by jsonPath does not exist, it is automatically created as needed.

Returns 1 for success, 0 for failure.

function UpdateSb(jsonPath: WideString; sb: TChilkatStringBuilder): Integer;

Introduced in version 9.5.0.68

Updates or appends a new string member with the contents of sb. If the full path specified by jsonPath does not exist, it is automatically created as needed.

Returns 1 for success, 0 for failure.

function UpdateString(jsonPath: WideString; value: WideString): Integer;

Introduced in version 9.5.0.63

Updates or appends a new string member. If the full path specified by jsonPath does not exist, it is automatically created as needed.

Important: Prior to version 9.5.0.68, the string passed in to this method did not get properly JSON escaped. This could cause problems if non-us-ascii chars are present, or if certain special chars such as quotes, CR's, or LF's are present. Version 9.5.0.68 fixes the problem.

Returns 1 for success, 0 for failure.

JSON UpdateString