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If the value for the "InputString" parameter should not be embedded in the task and the value would be given on execution time, for example when executing the task from the User Portal, then an IN argument is defined for the "InputString" parameter. The arguments are defined in the Task Designer panel, Parameters section, Arguments tab. Each argument defined in this section should have a name, direction( IN for input values , OUT for output values, IN/OUT for arguments that are used for both input and output purposes). The argument type must match the desired input parameter's type from the activity (for example, for Length activity, the InputString parameter has a string type, so the defined argument InputString should have the same type).
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