VuGen

1.How to perform basic operations in parameters

LoadRunner functions and scripts, containing in the present article, will be interested for LoadRunner beginners in the first place.

I will describe - how to perform basic mathematical operations on LoadRunner parameters:

• How to convert LoadRunner parameter's value to integer number?
• How to save integer number to LoadRunner parameter?
• How to perform mathematical operations on LoadRunner parameter?
  

You can use this article as a LoadRunner tutorial on LoadRunner parameter operations.
Well... May I start? :)

1. How to convert LoadRunner parameter's value to integer number?
   
   Actually, this is not a difficult task. We have to use 'atoi' function.
   'atoi' function converts a string to an integer value.
   
   Please, see the following code:
   
   
   

   1. lr_save_string("543210", "prmCounter");
   2. lr_output_message("String value of prmCounter: %s", lr_eval_string("{prmCounter}"));
   3. 
      
   4. i = atoi(lr_eval_string("{prmCounter}"));
   5. 
      
   6. lr_output_message("Integer value of prmCounter: %d", i);
      
      
   
   The result is:
   The key line of code is:
   
   
   

   1. i = atoi(lr_eval_string("{prmCounter}"));
      
      
   We get parameter's string value using lr_eval_string function and after that atoi function converts it to int value. Apparently, it is easy :)
   
   
   
2. How to save integer number to LoadRunner parameter?
   
   There are several way how to convert integer and save it to parameter.
   
   
   1. lr_save_int function. It saves an integer to a parameter.
      Code is very simple:
      
      
      

      1. int i;
      2. 
         
      3. i = 433;
      4. lr_save_int(i, "prmCounter");
      5. 
         
      6. lr_output_message("String value of prmCounter: %s", lr_eval_string("{prmCounter}"));
         
         
      
      The result is:
      
      
   2. sprintf function. It writes formatted output to a string. Then we use lr_save_string function to save the string to parameter:
      
      
      

      1. int i;
      2. char szBuf[12];
         
      3. 
         
      4. i = 118;
      5. sprintf(szBuf, "%d", i);
      6. lr_save_string(szBuf, "prmCounter");
         
      7. 
         
      8. lr_output_message("String value of prmCounter: %s", lr_eval_string("{prmCounter}"));
         
         
      
      The result is:
      
      
   3. itoa function. It converts an integer to a string. And then we use lr_save_string function to save the string to parameter:
      
      
      

      1. int i;
      2. char szBuf[12];
         
      3. 
         
      4. i = 27;
      5. itoa(i, szBuf, 10);
      6. lr_save_string(szBuf, "prmCounter");
         
      7. 
         
      8. lr_output_message("String value of prmCounter: %s", lr_eval_string("{prmCounter}"));
         
         
      
      The result is:
      

2. LoadRunner VIDEO tutorial - Parameters part1 ('Select next row' = 'Sequential')

3. LoadRunner VIDEO tutorial - Parameters part2 ('Select next row' = 'Random')

4. LoadRunner VIDEO tutorial - Parameters part3 ('Select next row' = 'Unique')