Capture dynamic data and write it to an external file in LoadRunner

To capture dynamic data and write it to an external file in LoadRunner, you can use the web_reg_save_param function to capture the data and the standard C file I/O functions to write it to a file. Here's an sample code of mine.

Action()
{
char *dynamic_data;
web_reg_save_param("dynamic_data", "LB=<start>", "RB=<end>", LAST);
// Make the request that returns the dynamic data

web_url("example.com", "URL=http://example.com/", "Resource=0", "RecContentType=text/html", "Referer=", "Snapshot=t1.inf", "Mode=HTML", LAST);

// Retrieve the captured dynamic data

dynamic_data = lr_eval_string("{dynamic_data}");

// Write the captured data to a file

FILE *fp = fopen("output.txt", "w"); // Replace "output.txt" with your desired file name
if (fp != NULL)
{
fputs(dynamic_data, fp);
fclose(fp);
}
else
{
lr_error_message("Failed to open file for writing.");
}
return 0;
}

Here the web_reg_save_param will capture the dynamic data between the specified left and right boundaries, and store it in a parameter named "dynamic_data". Then, we make a request that returns the dynamic data, causing it to be captured and saved in the parameter. Next, we retrieve the captured dynamic data using lr_eval_string and store it in the dynamic_data variable. Finally, we use standard C file I/O functions to open a file named "output.txt" for writing, write the dynamic data to the file using fputs, and then close the file using fclose.