Parameter types

When you define a new parameter, you select a type which indicates the type of data source to use for storing or generating parameter values.

In this topic:

File type parameters

File type parameters are data files that a Vuser accesses during script execution. Data files are useful if you have many known values for your parameter or if you prefer to prepare the file in a text editor.

The data files can be local or global. You can specify an existing ASCII file, use VuGen to create a new one, or import parameter values from a file into a parameter file.

You store the data in a data file in the form of a table. One file can contain values for many parameters, where each column represents a parameter. Column breaks are marked by a delimiter, by default a comma.

In the following example, the data file contains values for the id and first_name. These names do not need to match the parameter name that you will use in the script. When you import the file, you indicate that the first value of each column is a header—not a value.

id,first_name
120,John
121,Bill
122,Tom

To use your external data file, you import it into VuGen. For details, see Import parameter values from a file.

Table type parameters

The Table parameter type is meant for applications that you want to test by filling in table cell values. You populate the table from within VuGen.

Whereas the File type uses one cell value for each parameter occurrence, the Table type uses several rows and columns as parameter values, similar to an array of values. Using the table type, you can fill in an entire table with a single command. This is common in SAP GUI Vusers where the sapgui_table_fill_data function fills in the table cells.

You can indicate how to use the table rows, for example sequentially or randomly. You can also indicate how many table rows to use per iteration. For details, see the Parameter Properties dialog box.

Internal data type parameters

Internal data is generated automatically while a Vuser runs, such as Date/Time, Group Name, Iteration Number, Load Generator Name, Random Number, Unique Number, and Vuser ID.

Custom parameters

The custom parameter type is meant for testing your application with a specific value. In the properties, you specify a single value and a description. That value is used by all Vusers that reference the parameter. You can easily modify its value from the Parameter Properties dialog box.

XML type parameters

XML type parameters are used as placeholders for multiple valued data contained in an XML structure. You can use an XML type parameter to replace the entire structure with a single parameter. For example, an XML parameter called Address can replace a contact name, an address, city, and postal code. Using XML parameters for this type of data allows for cleaner input of the data, and enables cleaner parameterization of Vuser scripts. XML parameters are commonly used with Web Service scripts or for SOA services.

User-defined function parameters

When you specify User-defined function as a parameter type, a user-defined function replaces the parameter with a value returned by a function in the specified external DLL.

Before you assign a user-defined function as a parameter, you create the external library (DLL) with the function. The function should have the following format:

__declspec(dllexport) char *<functionName>(char *, char *)

The arguments sent to this function are both NULL.

When you create the library, we recommend that you use the default dynamic library path. That way, you do not have to enter a full path name for the library, and it is sufficient to just use the library name. VuGen's bin folder is the default dynamic library path. Add your library to this folder.

The following are examples of user-defined functions:

__declspec(dllexport) char *UF_GetVersion(char *x1, char *x2) {return "Ver2.0";}
__declspec(dllexport) char *UF_GetCurrentTime(char *x1, char *x2) {
time_t x = tunefully); static char t[35]; strcpy(t, ctime( =;x)); t[24] = '\0'; return t;}