TcSymbol | tc-context

Class representing an instance of a PLC Symbol, mapped to the TcContext. The TcSymbol itself acts as a bridge to the TcBinding, which has the responsibility of low-level ADS operations.

NOTE: In order to avoid naming collisions with the Symbols declared in the Target PLC, all public methods of TcSymbol start with the '$' character.

The TcSymbol should not be directly created, as it serves as a Template for the Derived TcSymbols

Hierarchy

TcSymbol

Indexable

[key: string]: TcSymbol | TcSymbolMethod

TcSymbols are indexable, in case they are structured types, and can nest children TcSymbols. Alternatively, if a TcSymbol has Rpc Methods enabled, this methods can be also invoked over the index.

NOTE: In order to avoid naming collisions with the Symbols declared in the Target PLC, all public methods of TcSymbol start with the '$' character.

The TcSymbol should not be directly created, as it serves as a Template for the Derived TcSymbols

Index

Constructors

constructor

Events

Accessors

Methods

Constructors

constructor

new TcSymbol(path: string, parent?: TcSymbol, readOnly?: boolean, debug?: boolean): TcSymbol

- Defined in src/tc-symbol.ts:68
Constructs the foundation of a TcSymbol Object

Parameters
- path: string
  
  The Path of this Symbol, relative to its origin point
- Optional parent: TcSymbol
  
  Potential parent of this TcSymbol and to whom events will propagate to
- Default value readOnly: boolean = false
  
  Flag which marks this TcSymbol as a ReadOnly symbol, and no operation of write-type can be issued to the TcSymbol
- Default value debug: boolean = false
  
  If enabled, will produce debug information
Returns TcSymbol

Events

$on

$on(event: "set", listener: (e: TcSymbolSetEvent) => void): TcSymbol
$on(event: "get", listener: (e: TcSymbolGetEvent) => void): TcSymbol
$on(event: "cleared", listener: (e: TcSymbolClearedEvent) => void): TcSymbol
$on(event: "changed", listener: (e: TcSymbolChangedEvent) => void): TcSymbol

- Defined in src/tc-symbol.ts:238
Emitted from TcBinding of a TcSymbol when TcSymbol.$set() has completed

Parameters
- event: "set"
- listener: (e: TcSymbolSetEvent) => void
  - - (e: TcSymbolSetEvent): void
    - Parameters
      - e: TcSymbolSetEvent
      Returns void
Returns TcSymbol
- Defined in src/tc-symbol.ts:245
Emitted from TcBinding of a TcSymbol when TcSymbol.$get has completed

Parameters
- event: "get"
- listener: (e: TcSymbolGetEvent) => void
  - - (e: TcSymbolGetEvent): void
    - Parameters
      - e: TcSymbolGetEvent
      Returns void
Returns TcSymbol
- Defined in src/tc-symbol.ts:252
Emitted from TcBinding of a TcSymbol when TcSymbol.$clear() has completed

Parameters
- event: "cleared"
- listener: (e: TcSymbolClearedEvent) => void
  - - (e: TcSymbolClearedEvent): void
    - Parameters
      - e: TcSymbolClearedEvent
      Returns void
Returns TcSymbol
- Defined in src/tc-symbol.ts:259
Emitted from TcBinding of a TcSymbol when TcSymbol detects a change in the PLC Symbol

Parameters
- event: "changed"
- listener: (e: TcSymbolChangedEvent) => void
  - - (e: TcSymbolChangedEvent): void
    - Parameters
      - e: TcSymbolChangedEvent
      Returns void
Returns TcSymbol

Accessors

$binding

get $binding(): TcSymbolBinding

- Defined in src/tc-symbol.ts:103
Access the TcBinding information of this TcSymbol

Returns TcSymbolBinding

$get

get $get(): Promise<any>

- Defined in src/tc-symbol.ts:124
Returns the value of this TcSymbol from the Target PLC Symbol, which the TcSymbol.$binding is linked to.

throws

TcBindingIsInvalidException - Attempting operation on an invalidated TcBinding

throws

TcComIsInvalidException - Attempting operation on an invalidated TcCom Object

throws

TcComDataReadException - An error occurred when fetching the Symbol Data

throws

TcComFromRawException - An error occurred when parsing Data to values

throws

TcBindingOutOfRangeException - Error occurred when parsing returned Data from the Target PLC Symbol

Returns Promise<any>
- The value of the Target PLC Symbol

$parent

get $parent(): TcSymbol | undefined

- Defined in src/tc-symbol.ts:91
Access the potential parent of this TcSymbol

Returns TcSymbol | undefined

$path

get $path(): string

- Defined in src/tc-symbol.ts:97
Access the path of this TcSymbol from its origin point

Returns string

$readOnly

get $readOnly(): boolean

- Defined in src/tc-symbol.ts:109
Returns true if this TcSymbol is ReadOnly

Returns boolean

Methods

$clear

$clear(): Promise<void>

- Defined in src/tc-symbol.ts:174
Clears the data of the Target PLC Symbol to their implicit default values, or the explicitly specified ones

throws

TcBindingIsInvalidException - Attempting operation on an invalidated TcBinding

throws

TcComIsInvalidException - Attempting operation on an invalidated TcCom Object

throws

TcComDataWriteException - An error occurred when writing the Symbol Data

throws

TcBindingReadOnlyException - Attempted to clear a ReadOnly Symbol

Returns Promise<void>

$off

$off(eventName: string, listener: (e: any) => void): TcSymbol

- Defined in src/tc-symbol.ts:275
Removes a listener from the specified event

Parameters
- eventName: string
  
  The event name, from which the listener is to be removed
- listener: (e: any) => void
  
  The listener, which is to be removed from the specified event
  - - (e: any): void
    - Parameters
      - e: any
      Returns void
Returns TcSymbol

$onInvalidated

$onInvalidated(callback: (symbol: TcSymbol) => void): void

- Defined in src/tc-symbol.ts:227
Attached the provided callback, which will be called when the `TcSymbol becomes invalidated

Parameters
- callback: (symbol: TcSymbol) => void
  
  The function, which is to be called upon invalidation
  - - (symbol: TcSymbol): void
    - Parameters
      - symbol: TcSymbol
      Returns void
Returns void

$once

$once(eventName: string, listener: (e: any) => void): TcSymbol

- Defined in src/tc-symbol.ts:289
Attached a listener to an event, which is only invoked once. For the full list of events, see TcSymbol.$on()

Parameters
- eventName: string
  
  The event name, which the listener will listen for
- listener: (e: any) => void
  
  The listener, which is called when the event is emitted
  - - (e: any): void
    - Parameters
      - e: any
      Returns void
Returns TcSymbol

$set

$set(value: any): Promise<any>

- Defined in src/tc-symbol.ts:153
Writes the provided value to the Target PLC Symbol, and when completed returns what was written to the Target PLC Symbol

throws

TcBindingIsInvalidException - Attempting operation on an invalidated TcBinding

throws

TcComIsInvalidException - Attempting operation on an invalidated TcCom Object

throws

TcComToRawException - An error occurred when parsing values to Data

throws

TcComDataWriteException - An error occurred when writing the Symbol Data

throws

TcBindingOutOfRangeException - Attempted to write a value to a non-existent field

throws

TcBindingInvalidTypeException - Type-mismatch occurred when parsing Values to Data

throws

TcBindingReadOnlyException - Attempted to write to a ReadOnly Symbol

Parameters
- value: any
  
  The value that is to be written to the Target PLC Symbol
Returns Promise<any>
- The value which was written to the Target PLC Symbol

$subscribe

$subscribe(sampling?: number): Promise<void>

- Defined in src/tc-symbol.ts:197
Activates value change detection of the Target PLC Symbol. The sampling rate can be explicitly set, in case the value changes uneseceraly too fast.

throws

TcBindingIsInvalidException - Attempting operation on an invalidated TcBinding

throws

TcComIsInvalidException - Attempting operation on an invalidated TcCom Object

throws

TcComSubscribeException - An error occurred when subscribing to the Symbol

Parameters
- Default value sampling: number = 10
  
  The speed at which change in the Target PLC Symbol value is detected
Returns Promise<void>

$unsubscribe

$unsubscribe(): Promise<void>

- Defined in src/tc-symbol.ts:215
Deactivated value change detection of the Target PLC Symbol. Does not remove the event handlers though, they simply will not be invoked.

throws

TcBindingIsInvalidException - Attempting operation on an invalidated TcBinding

throws

TcComIsInvalidException - Attempting operation on an invalidated TcCom Object

throws

TcComUnsubscribeException - An error occurred when unsubscribing for a Symbol

Returns Promise<void>

Protected __invalidate

__invalidate(): void

- Defined in src/tc-symbol.ts:310
Invalidates the TcBindingof this symbol, as well as, if a callback as provided in case of invalidation - will invoke it

Returns void

Hierarchy

Indexable

Index

Constructors

Events

Accessors

Methods

Constructors

constructor

Parameters

path: string

Optional parent: TcSymbol

Default value readOnly: boolean = false

Default value debug: boolean = false

Returns TcSymbol

Events

$on

Parameters

event: "set"

listener: (e: TcSymbolSetEvent) => void

Parameters

e: TcSymbolSetEvent

Returns void

Returns TcSymbol

Parameters

event: "get"

listener: (e: TcSymbolGetEvent) => void

Parameters

e: TcSymbolGetEvent

Returns void

Returns TcSymbol

Parameters

event: "cleared"

listener: (e: TcSymbolClearedEvent) => void

Parameters

e: TcSymbolClearedEvent

Returns void

Returns TcSymbol

Parameters

event: "changed"

listener: (e: TcSymbolChangedEvent) => void

Parameters

e: TcSymbolChangedEvent

Returns void

Returns TcSymbol

Accessors

$binding

Returns TcSymbolBinding

$get

Returns Promise<any>

$parent

Returns TcSymbol | undefined

$path

Returns string

$readOnly

Returns boolean

Methods

$clear

Returns Promise<void>

$off

Parameters

eventName: string

listener: (e: any) => void

Parameters

e: any

Returns void

Returns TcSymbol

$onInvalidated

Parameters

callback: (symbol: TcSymbol) => void

Parameters

symbol: TcSymbol

Returns void

Returns void

$once

Parameters

eventName: string

listener: (e: any) => void

Parameters

e: any