在LoadRunner中使用文件的相关函数

在LoadRunner测试过程中，有时候需要使用文件，可以封装出几个常用的文件操作函数。

参考：

http://www.jds.net.au/tech-tips/vugen-code-snippets/

/*

Writes a string to the end of a file.

Arguments:

- file_name: Include the full path in the file name, and escape any slashes. E.g. "C://TEMP//output.txt". Note that file does not have to exist beforehand, but directory does.

- string: If attempting to write a single line, include a newline character at the end of the string.

Returns 0 on success. On failure, function will raise lr_error_message and return -1.

*/

int jds_append_to_file(char* file_name, char* string) {

int fp; // file pointer

int rc; // return code

int length = strlen(string);

// Check that file_name is not NULL.

if (file_name == NULL) {

lr_error_message("Error. File name is NULL");

return -1;

}

fp = fopen(file_name, "a"); // open file in "append" mode.

if (fp == NULL) {

lr_error_message("Error opening file: %s", file_name);

return -1;

}

rc = fprintf(fp, "%s", string);

if (rc != length) {

lr_error_message("Error writing to file: %s", file_name);

return -1;

}

rc = fclose(fp);

if (rc != 0) {

lr_error_message("Error closing file: %s", file_name);

return -1;

}

return 0;

}

//////////////////////////////////////////////////////////////////////////////////////////////

// Checks if a file already exists on the filesystem.

// Arguments:

// - file_name: Include the full path in the file name.

// Returns TRUE (1) if file exists and user has read access to the file, otherwise function returns FALSE (0).

int jds_file_exists(char* file_name) {

int fp; // file pointer

fp = fopen(file_name, "r+"); // open file in read mode. File must already exist.

if (fp == NULL) {

return FALSE;

} else {

fclose(fp);

return TRUE;

}

}

//////////////////////////////////////////////////////////////////////////////////////////////

// Saves a file to the hard disk.

// Arguments:

// - file_name: Include the full path in the file name. Note that file must not exist before function is called.

// - file_content: The data to save to the file. Can be binary or string data.

// - file_size: The size/length of the data to save to the file. If it is string data, you can find this using strlen(). If you are saving binary data from a web page, use web_get_int_property(HTTP_INFO_DOWNLOAD_SIZE).

// Returns 0 on success. On failure, function will raise lr_error_message and return -1.

int jds_save_file(char* file_name, void* file_content, unsigned int file_size) {

int rc; // function return code

int fp; // file pointer

// Check input values

if (file_name == NULL) {

lr_error_message("File name is NULL");

return -1;

} else if (file_content == NULL) {

lr_error_message("File content is NULL");

return -1;

} else if (file_size < 1) {

lr_error_message("Invalid file size: %d", file_size);

return -1;

}

// Does the file already exist?

if (jds_file_exists(file_name) == TRUE) {

lr_error_message("File %s already exists", file_name);

return -1;

}

fp = fopen(file_name, "wb"); // open file in "write, binary" mode.

if (fp == NULL) {

lr_error_message("Error opening file: %s", file_name);

return -1;

}

rc = fwrite(file_content, file_size, 1, fp);

if (rc != 1) {

lr_error_message("Error writing to file. Items written: %d", rc);

return -1;

}

rc = fclose(fp);

if (rc != 0) {

lr_error_message("Error closing file: %s", file_name);

return -1;

}

return 0;

}

//////////////////////////////////////////////////////////////////////////////////////////////

使用的例子：

Action()

{

int is_exists=0;

char *str = "string to write!";

char *file= "D://test.txt";

is_exists = jds_file_exists( file );

//lr_save_int(is_exists,"File_Exist");

//lr_output_message(lr_eval_string("{File_Exist}"));

if(is_exists)

{

jds_append_to_file(file,str);

}

else

{

jds_save_file(file,str,strlen(str));

}

return 0;

}

在LR的帮助文档中，也有关于文件、目录操作函数的详细介绍：

Function Name	Description
chdir	Changes the current directory to the given path.
chdrive	Switches to another drive.
getcwd	Returns the name of the current working directory.
getdrive	Returns the name of the current drive.
mkdir	Creates a directory using the given path name.
remove	Deletes the specified file.
rmdir	Deletes the specified directory.

Function Name	Description
fclose	Closes a file.
feof	Checks if the end of file has occurred on a stream.
ferror	Checks if any error has occurred during file I/0.
fgetc	Gets a character from a stream.
fgets	Reads a string from a file.
fopen	Opens a file for buffered I/0.
fprintf	Writes formatted output to a file.
fputc	Writes a character to a stream.
fread	Reads unformatted data from a stream into a buffer.
fscanf	Reads formatted input from a stream.
fseek	Sets the current position in a file to a new location.
fwrite	Write unformatted data from a buffer to a stream.
rewind	Rewinds a file.
sprintf	Writes formatted output to a string.
sscanf	Reads formatted input from a string.