This tutorial explains how a Flash movie can retrieve data
from an external text file. To understand this tutorial, it's
recommended that you are already familiar with:
how to access variables in Flash
Flash Action Scripting
Flash 4 (and newer) has a capability to retrieve the content of a
text file by using the LoadVariables function. This is quite powerful,
for example, you can create a news engine without manually
editing the FLA file every time the news changes.
The process of reading the file is relatively straightforward and simple, but there are
some details to be aware of.
The text file must be in the standard ASCII format (text-plain).
means that you cannot use Word, html, or any format other than
plain-text. Flash would not understand embedded formatting
such as found in Word, or excel files.
The text file must contain variables in CGI-encoded (MIME) format. Basically, this means
2 things. First, you need to pass the data as variable(s) -
more on this below. Second, there are special
characters that need to be represented differently (encoded), for example
<SPACE> should be represented with "+" or
"%20", although Flash 4 does not seem to enforce this
(see text file example below).
It might take a while to transfer the data. So if the Flash movie is supposed to
further processing with the data, make sure to check whether the data has been received or not.
More information about item 2 and 3 can be read here.
As an example, this is a text file, it's called text.txt (this name is just an example, you can use any valid
file-name, the extension does not have to be ".txt", but it
has to contain plain-text). text.txt
There are 3 variables in this file:
All the variable names are followed by a "=" sign, and
an "&"sign acts as separator between variableName=variableValue
pairs. These are part of the MIME requirements mentioned in item 2
above. Please be sure that you can spot those variables
before continuing. (Note that there can't be any
<SPACE> on a variable name.)
Again, notice how the & and = communicate special
meanings. What if I need to use "&" and "="
character as part of the data? This is where you most likely
need to use MIME encoding. In that case, you need to replace
the special character with a % sign, followed by the
For example, notice, the variable header has %20, which represent
a <SPACE>. Also, notice that the theText
variable contains %26 .... which doesn't quite make sense
to be there, but that number actually represents a & character.
Those numbers are ASCII numbers (hexadecimal code of the character). If you
need to know the ASCII-value for a particular character, consult
an ASCII table; this is a standard programmer reference that
should be easy to find on the web.
Now, back to the variables. For the sake of this
example, I will be using those variables to create a news site, so
header contains the title of the news
theText contains the content of the news
done is a flag that can be used to check whether the data has been transferred or not. This kind of flag should be placed at the end of the data.
The reason is because the data transfer will be sequential, and if
this flag is being
sent elsewhere other than at the end of the data stream, the Flash
mistakenly think the whole file has been transferred, when
actually only part of it has. (You do not need to have any flag if the Flash movie is not going need the data to do some
These variable names are arbitrary, but don't use <space> or
any special character as part of a variable name (another MIME
To read the text file, I created a very simple Flash movie. The movie is
shown below. You should see the content of the the text
file (or the news, if you will) there.
The Flash Movie (a fake
Side note: If you are still perplexed by the MIME business,
here's more... Notice how Flash converted the %20 and the +
sign in the header variable to <SPACE> character.
notice that %26 is converted into a & character. (Compare
the content of the text file with what is displayed in the movie.)
This Flash movie uses LoadVariables to
"read" the text file, as shown in the picture below. When
this LoadVariables is executed, the text file will be read. Once
the data transfer is complete (i.e.: the text file is completely
read), then the Flash movie will have 3 variables: header, theText,
and done. Note: It is not necessary to manually create
these variables in the Flash movie; Flash will create them
automatically - if they already exists, the values will be
(If you don't quite understand the parameters of
LoadVariables, an explanation can be found on
this other tutorial. Using Send using GET or Send using POST prevents the data from being
cached by the browser.) Caching problem can be a serious issue,
please see Caching
To display the data, I purposefully created two
editable text-fields with the Variable Property set to the same
variable names as in the text file.
Specifically, the first text field has the Variable
property set to header (shown below); and the next text field
is set to theText. Remember that Flash will automatically
update a text field with the specified variable, so this really is a
quick and convenient way to display the content of the text
Flash 4: The crosshatched rectangle highlights a editable text field, named
Flash 5: The blue rectangle highlights a Dynamix Text field, named
The "header" text field will contain the string
"Vacation Is Good" once the text file is loaded. Flash
knows what value to put there because the string "Vacation Is
Good" is assigned to variable "header" in the
You can load more than one text file on
a single Flash movie.
To test the Movie, you must use "Publish
Preview->html," using the "Test Movie" menu will
You can now download Flash 4 and Flash 5 FLA files
here: Flash 4