Invokes a method or action on a VI, VI object, or application. Most methods have associated parameters. If the node is configured for VI Server Application class or Virtual Instrument class and reference is unwired, reference defaults to the current Application or VI. Details
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reference in is the refnum associated with the open VI, VI object, or application on which you want to invoke a method or perform an action. | ||||||
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error in describes error conditions that occur before this VI or function runs.
The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurs before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node.
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input 1..n is an example input parameter of a method. | ||||||
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dup reference returns reference unedited. | ||||||
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error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces.
Right-click the error out indicator on the front panel and select Explain Error from the shortcut menu for more information about the error.
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return value is an example return value of a method. | ||||||
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output 1..n is an example output parameter of a method. |
To select the VI, Control, or Application class, wire the VI, VI object, or application refnum to reference and the node adapts to the class. You also can right-click the node and select a Select Class submenu.
Right-click the node and select Help For Method from the shortcut menu, where Method is the name of the method, for more information about the method and its parameters.
You can get (read) and set (write) the values of the method parameters. Parameters with a white background are required inputs and the parameters with a gray background are recommended inputs.
If the small direction arrow on the parameter is on the right, you are getting the parameter value. If the small direction arrow on a parameter is on the left, you are setting the parameter value. To display only the data type for each parameter, right-click and select Name Format»No Names from the shortcut menu.