MarshySwamp

/* Remove Filename Extension (4 different methods) */

var baseName = app.activeDocument.name.split('.')[0];

// or for multiple period characters

var extensionIndex = activeDocument.name.lastIndexOf(".");
if (extensionIndex != -1) {
    var baseName = activeDocument.name.substr(0, extensionIndex);
    alert(baseName);

MarshySwamp

// Save the current ruler units and set to pixels
var savedRuler = app.preferences.rulerUnits;        
app.preferences.rulerUnits = Units.PIXELS;
// Do stuff...
// Restore the ruler units
app.preferences.rulerUnits = savedRuler;    

// Save the current dialog display settings
var savedDisplayDialogs = app.displayDialogs;
app.displayDialogs = DialogModes.NO;

MarshySwamp

/* Start Open Document Error Check - Part A: If */
if (app.documents.length > 0) {

  /* Main Code Start */

  alert('Do something here!');

  /* Main Code Finish */
}
/* Finish Open Document Error Check - Part A: If */

MarshySwamp

if (!documents.length) {
   alert('There are no documents open.', 'No Document');

} else {
   alert('You have a document open!');
}

// or

if (app.documents.length > 0) {

MarshySwamp

// Remove ' px' from document width and height
app.preferences.rulerUnits = Units.PIXELS;
var w = app.activeDocument.width.toString().replace(' px', '');
var h = app.activeDocument.height.toString().replace(' px', '');

//or
var w = app.activeDocument.width.value;
var h = app.activeDocument.height.value;

//or

MarshySwamp

// remove all paths
app.activeDocument.pathItems.removeAll();
 
// remove all alphas
app.activeDocument.channels.removeAll();
 
// remove all layercomps
app.activeDocument.layerComps.removeAll();
 
// remove all color samplers

MarshySwamp

// Move the current layer in 5px from the right and down 5px from the top
app.activeDocument.activeLayer.translate( -5, 5 );

MarshySwamp

app.doAction("Molten Lead","Default Actions.atn");

// or

var actionName = "Molten Lead"; // Action to run
var actionSet = "Default Actions.atn"; // Action set to run
app.doAction(actionName,actionSet);

// or

MarshySwamp

/* An example of running a menu item command.
Use Script Listener to find the menu name, often by inserting the menu command into an action */


// Collapse all layer groups/sets
app.runMenuItem(stringIDToTypeID('collapseAllGroupsEvent'));

// another example:

// More info:

MarshySwamp

// Deselect All Layers  
// forums.adobe.com/message/5204655#5204655 - Michael L Hale  
app.runMenuItem(stringIDToTypeID('selectNoLayers'));

// Or...

// Deselect All Layers (AM Code Through Clean SL)
selectNoLayers();
function selectNoLayers() {
	var c2t = function (s) {