RAPID variables & symbols
Read and write RAPID variables, persistents and constants, search symbols in the loaded program, and validate a value before writing it.
A RAPID symbol is anything the program declares: a variable, a persistent, a constant, a routine, a type, a module, a task. robot.Rws.Rapid reads and writes them by their path, with the same two methods for every RAPID type.
Reading a value needs nothing more than a connection. Writing one needs the Rapid mastership.
The path of a symbol
Every symbol has a path. It starts with RAPID, then the task, then the module, then the name. This path is what GetSymbolValue and SetSymbolValue take.
AbbController robot = new AbbController();robot.Connect("192.168.0.1");// A variable declared in the module MainModule of the task T_ROB1robot.Rws.Rapid.GetSymbolValue("RAPID/T_ROB1/MainModule/myCounter");// reg1 and the other predefined registers live in the built-in module "user"robot.Rws.Rapid.GetSymbolValue("RAPID/T_ROB1/user/reg1");// A leading slash is accepted, it is removed by the SDKrobot.Rws.Rapid.GetSymbolValue("/RAPID/T_ROB1/user/reg1");// A module of the task, and the task itself, are symbols toorobot.Rws.Rapid.GetSymbolProperties("RAPID/T_ROB1/MainModule");robot.Rws.Rapid.GetSymbolProperties("RAPID/T_ROB1");// A RAPID type has a path of its own, without any taskrobot.Rws.Rapid.GetSymbolProperties("RAPID/robtarget");robot.Disconnect();}
| Path | What it names |
|---|---|
RAPID/T_ROB1/MainModule/myCounter | A variable, a persistent or a constant of a module |
RAPID/T_ROB1/user/reg1 | reg1 to reg5, which live in the built-in module user |
RAPID/T_ROB1/MainModule | The module itself |
RAPID/T_ROB1 | The task itself |
RAPID/robtarget | A RAPID type, which belongs to no task |
The path is case sensitive on the name of the module and on the name of the symbol. A leading slash is accepted, the SDK removes it. When no symbol has that path, the controller answers 404 and the SDK throws an RwsException.
If you do not know where a variable is declared, do not guess the path, search for it with SearchSymbols.
Read a value
GetSymbolValue returns the value as the text RAPID writes it with, plus where the declaration sits in the module. There is no typed overload, a num, a bool and a robtarget all come back as a string.
AbbController robot = new AbbController();robot.Connect("192.168.0.1");// A value always comes back as the text RAPID writes it with. Reading needs no mastership.RapidSymbolValue value = robot.Rws.Rapid.GetSymbolValue("RAPID/T_ROB1/user/reg1");Console.WriteLine(value.Value); // "42"Console.WriteLine(value.DeclarationPosition); // where the declaration sits in the module// num and dnum: parse with the invariant culture, RAPID uses a dot as decimal separatordouble number = double.Parse(robot.Rws.Rapid.GetSymbolValue("RAPID/T_ROB1/user/reg1").Value,CultureInfo.InvariantCulture);// bool: the controller writes TRUE or FALSEbool flag = robot.Rws.Rapid.GetSymbolValue("RAPID/T_ROB1/MainModule/myFlag").Value.Trim().Equals("TRUE", StringComparison.OrdinalIgnoreCase);// string: the value carries the RAPID quotes, remove themstring text = robot.Rws.Rapid.GetSymbolValue("RAPID/T_ROB1/MainModule/myText").Value.Trim('"');Console.WriteLine(number + " " + flag + " " + text);robot.Disconnect();}
| RAPID type | What Value holds |
|---|---|
num, dnum | 42, 1.5, 9E+09. Always a dot as decimal separator. |
bool | TRUE or FALSE, in capitals |
string | The RAPID quotes are part of the value, "hello" |
robtarget, pos, any record | The bracketed form, [[515,0,712],[1,0,0,0],[0,0,0,0],[9E+09,...]] |
| An array | One value too, [1,2,3] |
Parse the numbers with CultureInfo.InvariantCulture. On a machine configured with a French or a German locale, double.Parse("1.5") without it gives 15.
Write a value
SetSymbolValue takes the same text form. The controller checks the value against the type of the symbol and answers 400 when it does not match.
AbbController robot = new AbbController();robot.Connect("192.168.0.1");// Writing needs the RAPID mastership. Take it, write, give it back.robot.Rws.Mastership.Request(MastershipDomain.Rapid);try{// num: format with the invariant culture, "1,5" is refused, "1.5" is accepteddouble speed = 1.5;robot.Rws.Rapid.SetSymbolValue("RAPID/T_ROB1/user/reg1",speed.ToString(CultureInfo.InvariantCulture));// bool: TRUE or FALSE, in capitalsrobot.Rws.Rapid.SetSymbolValue("RAPID/T_ROB1/MainModule/myFlag", "TRUE");// string: the RAPID quotes are part of the valuerobot.Rws.Rapid.SetSymbolValue("RAPID/T_ROB1/MainModule/myText", "\"hello\"");}finally{robot.Rws.Mastership.Release(MastershipDomain.Rapid);}robot.Disconnect();}
What readers get wrong, in order:
- The mastership. Without the
Rapidmastership the controller answers 403. In manual mode it also wants the write access an operator grants from the FlexPendant. - The culture.
speed.ToString()on a French machine writes1,5, which the controller refuses. Always format withCultureInfo.InvariantCulture. - The quotes of a string. The value of a RAPID
stringcarries them,"\"hello\""and not"hello". - A constant. A
CONSTcannot be written while the program runs.GetSymbolPropertiesreports it, itsReadOnlyproperty istrue. - A local variable. A variable declared inside a routine only exists while the routine runs.
Writing a variable does not change the declaration. After a program reset the symbol goes back to the value written in its source, see below.
Methods of RapidService :// Gets the value of a RAPID symbol and where it is declared (synchronous)RapidSymbolValue GetSymbolValue(string symbolUrl);// Sets the value a RAPID symbol is declared with, which is the one it goes back to when the program is reset (synchronous)void SetSymbolInitialValue(string symbolUrl, string value);// Sets the value a RAPID symbol currently holds (synchronous)void SetSymbolValue(string symbolUrl, string value);
Every method also exists in an asynchronous version, with the same name followed by Async and an optional CancellationToken.
The value of a RAPID symbol and where it is declared. Returned by RapidService.GetSymbolValue(). The value is the text the controller wrote it as, which for a record is the bracketed form RAPID itself uses, for example [[515,0,712],[0.707107,0,0.707107,0],[0,0,0,0],[9E+09,9E+09,9E+09,9E+09,9E+09,9E+09]].
| Member | Type | Description |
|---|---|---|
RapidSymbolValue() Constructor | Initializes a new instance of the RapidSymbolValue class | |
DeclarationPosition Property | RapidTextRange | Where the symbol is declared, null when the controller did not report it |
InitialValuePosition Property | RapidTextRange | Where the initial value of the symbol is written, null when the controller did not report it. The controller reports zeros when the declaration carries no initial value. |
Value Property | string | Value of the symbol, written the way RAPID writes it |
ToString() Method | string | Returns a string representation of this value |
A span of source between two positions, counted from 1. Used wherever the controller reports where something is declared or where a statement sits.
| Member | Type | Description |
|---|---|---|
RapidTextRange() Constructor | Initializes a new instance of the RapidTextRange class | |
BeginColumn Property | int? | Column the range begins at, null when the controller did not report it |
BeginRow Property | int? | Line the range begins at, null when the controller did not report it |
EndColumn Property | int? | Column the range ends at, null when the controller did not report it |
EndRow Property | int? | Line the range ends at, null when the controller did not report it |
ToString() Method | string | Returns a string representation of this range |
Records, arrays and the initial value
A record is not taken apart by the SDK. You get the bracketed text, in the same order as the components of the type, and you write it back the same way.
AbbController robot = new AbbController();robot.Connect("192.168.0.1");// A record comes back in the bracketed form RAPID writes it with. The SDK does not// take it apart, you get the text and parse what you need.RapidSymbolValue target = robot.Rws.Rapid.GetSymbolValue("RAPID/T_ROB1/MainModule/pHome");Console.WriteLine(target.Value);// [[515,0,712],[0,0,1,0],[0,0,0,0],[9E+09,9E+09,9E+09,9E+09,9E+09,9E+09]]// An array is one value too, its elements separated by commasConsole.WriteLine(robot.Rws.Rapid.GetSymbolValue("RAPID/T_ROB1/MainModule/myArray").Value); // [1,2,3]// Build the text with the invariant culture, a comma as decimal separator is refuseddouble x = 515.5, y = 0, z = 712;string pose = string.Format(CultureInfo.InvariantCulture,"[[{0},{1},{2}],[0,0,1,0],[0,0,0,0],[9E9,9E9,9E9,9E9,9E9,9E9]]",x, y, z);robot.Rws.Mastership.Request(MastershipDomain.Rapid);try{// The value has to carry every component the type declaresrobot.Rws.Rapid.SetSymbolValue("RAPID/T_ROB1/MainModule/pHome", pose);}finally{robot.Rws.Mastership.Release(MastershipDomain.Rapid);}robot.Disconnect();}
SetSymbolInitialValue writes the value the declaration carries, the one the symbol goes back to when the program is reset. It rewrites the source of the module, so the module counts as changed afterwards. SetSymbolValue only changes what the symbol holds right now.
InitialValuePosition of RapidSymbolValue says where that initial value sits in the source. The controller reports zeros when the declaration carries none.
Check a value before writing it
ValidateSymbolValue asks the controller whether it would accept a value for a given type, without writing it anywhere. It returns false for a refused value instead of throwing, so it is what an editor uses to tell an operator that what they typed is wrong.
AbbController robot = new AbbController();robot.Connect("192.168.0.1");// Ask the controller whether it would take the value, without writing it anywhereConsole.WriteLine(robot.Rws.Rapid.ValidateSymbolValue("T_ROB1", "num", "1.5")); // true// A value that does not fit the type gives false, it does not throwConsole.WriteLine(robot.Rws.Rapid.ValidateSymbolValue("T_ROB1", "num", "hello")); // falserobot.Rws.Mastership.Request(MastershipDomain.Rapid);try{if (robot.Rws.Rapid.ValidateSymbolValue("T_ROB1", "num", "1.5"))robot.Rws.Rapid.SetSymbolValue("RAPID/T_ROB1/user/reg1", "1.5");// The value written in the declaration, the one the symbol goes back to when the// program is reset. This rewrites the source of the module.robot.Rws.Rapid.SetSymbolInitialValue("RAPID/T_ROB1/MainModule/myCounter", "0");}finally{robot.Rws.Mastership.Release(MastershipDomain.Rapid);}robot.Disconnect();}
Any other failure, a type that does not exist for example, is still reported as an RwsException.
// Asks the controller whether a value would be accepted for a given RAPID type, without writing it anywhere (synchronous) This is what an editor uses to tell an operator that what they typed is wrong before the write is attempted.bool ValidateSymbolValue(string task, string dataType, string value);
Every method also exists in an asynchronous version, with the same name followed by Async and an optional CancellationToken.
Search symbols
SearchSymbols walks the program and returns the symbols matching a set of criteria. It is the way to list the robtarget of a module, to find every persistent of a task, or to check that a variable exists before writing it.
AbbController robot = new AbbController();robot.Connect("192.168.0.1");// Always give a starting point, a search without any criterion walks the whole systemRapidSymbolSearchCriteria criteria = new RapidSymbolSearchCriteria();criteria.View = RapidSymbolSearchView.Block;criteria.BlockUrl = "RAPID/T_ROB1";criteria.Recursive = true;criteria.NamePattern = "^p[0-9]+$"; // regular expression on the namecriteria.DataType = "robtarget";// Only the first entry is sent, search again for another kindcriteria.SymbolTypes = new RapidSymbolType[] { RapidSymbolType.Persistent };foreach (RapidSymbolProperties symbol in robot.Rws.Rapid.SearchSymbols(criteria)){Console.WriteLine(symbol.Name + " (" + symbol.DataType + ")");// SymbolUrl is the path the other symbol methods takeConsole.WriteLine(robot.Rws.Rapid.GetSymbolValue(symbol.SymbolUrl).Value);}// What one symbol is declared as, without reading its valueRapidSymbolProperties properties = robot.Rws.Rapid.GetSymbolProperties("RAPID/T_ROB1/user/reg1");Console.WriteLine(properties.SymbolType); // Variable, Persistent, Constant, ...Console.WriteLine(properties.DataType); // numConsole.WriteLine(properties.ReadOnly); // null when the controller did not report itrobot.Disconnect();}
Always set BlockUrl. A search with no criterion at all walks the whole system and takes seconds.
RapidSymbolSearchView | Where the search looks |
|---|---|
Block | In the block named by BlockUrl, and in what it contains when Recursive is true |
Scope | In what is visible from a position of the source, which needs PositionRow and PositionColumn |
Stack | In what is visible from a frame of the call stack, which needs the program pointer to be set |
Undefined | Let the controller decide |
SymbolTypes filters on the kind of symbol: Variable, Persistent, Constant, Function, Procedure, Trap, Module, and the others of RapidSymbolType. The controller keeps only one kind per search, so only the first entry of the array is sent. Search once per kind when you need several.
NamePattern is a regular expression, not a wildcard. DataType takes the name of a RAPID type, for example robtarget.
GetSymbolProperties returns the same information for one symbol: its kind, its type, whether it is local to its module, whether it is read only. A property the controller did not report comes back as null, so test the nullable properties before using them.
// Gets what a RAPID symbol is declared as (synchronous)RapidSymbolProperties GetSymbolProperties(string symbolUrl);// Finds the RAPID symbols matching a set of criteria (synchronous)RapidSymbolProperties[] SearchSymbols(RapidSymbolSearchCriteria criteria);
Every method also exists in an asynchronous version, with the same name followed by Async and an optional CancellationToken.
What a RAPID symbol is declared as. Returned by RapidService.GetSymbolProperties() and RapidService.SearchSymbols(). A search fills in Name and leaves Storage alone, a direct read does the opposite on some controllers, so treat both as optional.
| Member | Type | Description |
|---|---|---|
RapidSymbolProperties() Constructor | Initializes a new instance of the RapidSymbolProperties class | |
DataType Property | string | Name of the type of the symbol, for example "num" |
Dimension Property | string | Size of each array dimension as the controller worded it, empty when the symbol is not an array |
Dimensions Property | int? | Number of array dimensions of the symbol, null when the controller did not report it |
Heap Property | bool? | Whether the symbol is allocated on the heap, null when the controller did not report it |
Linked Property | bool? | Whether the declaration is complete, null when the controller did not report it |
Local Property | bool? | Whether the symbol is local to its module, null when the controller did not report it |
Name Property | string | Name of the symbol, for example "reg1" |
Named Property | bool? | Whether the symbol is named, null when the controller did not report it |
ReadOnly Property | bool? | Whether the symbol may not be written, null when the controller did not report it |
Storage Property | string | How the controller stores the symbol, for example "loaded" |
SymbolType Property | RapidSymbolType | What kind of symbol this is |
SymbolUrl Property | string | Path of the symbol, which the other symbol methods take |
TaskVariable Property | bool? | Whether the symbol is global within its task, null when the controller did not report it |
TypeUrl Property | string | Path of the type of the symbol, for example "RAPID/num" |
ToString() Method | string | Returns a string representation of this symbol |
What a symbol search looks for. Passed to RapidService.SearchSymbols(). Every property is optional; leaving one alone means the search does not filter on it. A search with no criterion at all walks the whole system, which is slow, so at least set BlockUrl.
| Member | Type | Description |
|---|---|---|
RapidSymbolSearchCriteria() Constructor | Initializes a new instance of the RapidSymbolSearchCriteria class | |
BlockUrl Property | string | Path the search starts from, for example "RAPID/T_ROB1" |
DataType Property | string | Name of the type a symbol has to have to be kept, for example "robtarget" |
NamePattern Property | string | Regular expression the name of a symbol has to match to be kept |
OnlyUsed Property | bool? | Whether only the symbols the program actually refers to are kept, null to leave it to the controller |
PositionColumn Property | int? | Column the search starts from, used together with Scope |
PositionRow Property | int? | Line the search starts from, used together with Scope |
Recursive Property | bool? | Whether the search also walks what the starting point contains, null to leave it to the controller |
SkipShared Property | bool? | Whether the symbols shared between tasks are skipped, null to leave it to the controller |
StackFrame Property | int? | Frame of the call stack the search starts from, used together with Stack |
SymbolTypes Property | RapidSymbolType[] | Kinds of symbol the search keeps, empty to keep every kind |
VariableType Property | RapidSymbolVariableType | Which variables the search keeps, by what may be done with them |
View Property | RapidSymbolSearchView | Which part of the system the search walks |
What a RAPID symbol is: a value, a routine, a type or one of the structural elements of the language
| Name | Value | Description |
|---|---|---|
Alias | 4 | An alias of another type |
Any | 17 | Any of the other types, which a search uses to mean that it does not filter on the type |
Atomic | 2 | A built-in type such as num or string |
Constant | 6 | A constant |
ForVariable | 11 | The loop variable of a FOR statement |
Function | 12 | A function |
Label | 10 | A label |
Module | 15 | A module |
Parameter | 9 | A parameter of a routine |
Persistent | 8 | A persistent variable, whose value survives a restart |
Procedure | 13 | A procedure |
Record | 3 | A record type |
RecordComponent | 5 | One component of a record |
Task | 16 | A task |
Trap | 14 | A trap routine |
Undefined | 1 | The type is not defined |
Unknown | 0 | The controller reported a type this library does not know |
Variable | 7 | A variable |
Which part of the system a symbol search walks
| Name | Value | Description |
|---|---|---|
Block | 1 | Search the block the search path names, and optionally what it contains |
Scope | 2 | Search what is visible from a position of the source, which the search path and the position both have to be given for |
Stack | 3 | Search what is visible from a frame of the call stack, which needs the program pointer to be set |
Undefined | 0 | Let the controller decide |
Which variables a symbol search keeps, by what may be done with them
| Name | Value | Description |
|---|---|---|
Any | 4 | Any of them |
Loop | 3 | Only the loop variables |
ReadOnly | 2 | Only the variables that can be read but not written |
ReadWrite | 1 | Only the variables that can be read and written |
Undefined | 0 | Let the controller decide |
Persistent variables shared between tasks
A PERS declared in several tasks holds the same value in all of them, as long as the module is synchronized with the others. GetSyncPersStatus reports it, SyncPersistentVariables does the synchronization.
AbbController robot = new AbbController();robot.Connect("192.168.0.1");// A persistent declared in several tasks holds the same value everywhere, as long as// the module is synchronized with the other tasks declaring itConsole.WriteLine(robot.Rws.Rapid.GetSyncPersStatus("T_ROB1", "MainModule"));robot.Rws.Mastership.Request(MastershipDomain.Rapid);try{robot.Rws.Rapid.SyncPersistentVariables("T_ROB1", "MainModule");}finally{robot.Rws.Mastership.Release(MastershipDomain.Rapid);}robot.Disconnect();}
// Gets whether the persistent variables of a module are kept synchronized with the other tasks declaring them (synchronous)bool GetSyncPersStatus(string task, string module);// Synchronizes the persistent variables of a module with the other tasks declaring them (synchronous)void SyncPersistentVariables(string task, string module);
Every method also exists in an asynchronous version, with the same name followed by Async and an optional CancellationToken.
Errors you can expect
| Status | What happened |
|---|---|
| 400 | The value does not match the type of the symbol, or the number was formatted with a comma |
| 403 | Your connection does not hold the Rapid mastership, or the user account lacks the UAS grant |
| 404 | No symbol has that path. Check the case of the module and of the name. |
| 500 | The controller cannot do it in its current state, for example writing a local variable of a routine that is not running |
A complete example, with a num, a bool, a string and a robtarget, is given in Read & write RAPID variables.
The values of the RAPID symbols are the same on the two controller generations. The starting and stopping of the program that uses them is on RAPID tasks & program execution, and the source of the modules declaring them on RAPID modules & program files.
Try it in the demo application
The RAPID (RWS) page of the demo application exercises these calls against a live controller, without writing any code. It is shown in RAPID tasks & program execution.