Actionscript 3.0 Smooth character movement

Smooth Character Movement
In actionscript 3.0 when you program an object to move following a keypress, the object moves once then pauses before continue the moment. This is the way I have achieved smooth movement, not certain its the best or easiest way but anyway heres what I did:

Using the example of moving left

Under your 'keydown' function for the left key, type mLeft = true;
Then under your 'enterFrame' function, have an if statement saying:

if (moveLeft) {
myCharacter.x = myCharacter.x - 10;
}

Then, under your 'keyup' function for the left key, type mLeft = false;

You will need to define the following variables for the different keys:

var moveLeft:Boolean = false;
var moveRight:Boolean = false;
var moveUp:Boolean = false;
var moveDown:Boolean = false;

(the last two if you are moving the character up and down as well as left and right)

All the code:

//Defining the variables
var moveLeft:Boolean = false;
var moveRight:Boolean = false;
var moveUp:Boolean = false;
var mDown:Boolean = false;

//Adding Event listeners
stage.addEventListener(KeyboardEvent.KEY_UP, reportKeyUp);
stage.addEventListener(KeyboardEvent.KEY_DOWN, reportKeyDown);
stage.addEventListener(Event.ENTER_FRAME, EnterFrame);

//KeyDown function
function reportKeyDown(event:KeyboardEvent):void {
if (event.keyCode == Keyboard.LEFT) {
moveLeft = true;
}
if (event.keyCode == Keyboard.RIGHT) {
moveRight = true;
}
if (event.keyCode == Keyboard.UP) {
moveUP = true;
}
if (event.keyCode == Keyboard.DOWN) {
moveDOWN= true;
}
}

//Key Up Function
function reportKeyDown(event:KeyboardEvent):void {
if (event.keyCode == Keyboard.LEFT) {
moveLeft = false;
}
if (event.keyCode == Keyboard.RIGHT) {
moveRight = false;
}
if (event.keyCode == Keyboard.UP) {
moveUP = false;
}
if (event.keyCode == Keyboard.UP) {
moveDOWN = false;
}
}

//Enter Frame Function (this happens over and over repeatedly)
function EnterFrame(event:Event):void {
if (moveLeft){
myCharacter.x -= 10;
}
if (moveRight){
myCharacter.x +=10;
}
if (moveUp){
myCharacter.y -=10;
}
if (moveDown){
myCharacter.y +=10;
}

}
}

I *think* that this should work, if it doesn't I apologise and please comment and tell me what the error says or what is happening.