How do I quickly export a layer as a png file in Photoshop with extendscript

Hi r-bin,

I try your code, it works well by this simple script. However, I find sometimes the selection doesn't exported, and the quick export option in photoshop broken the same time. I need to restart photoshop to get the quick export feature works.

One situation is batch export. I want to export the layers under some layerSet. But the layer seems don't exported.

```

LayerSet

     LayerToExport 1 // when only one layer under LayerSet the export success, but fails on two layers

     LayerToExport 2

```

The other situation is snapshot. Before I export, I just create a snapshot, and after select and export ,I restore the snapshot, but it seems break the export too.

Some Code:

Situation one

```

selectLayer = function(layer) {
    var idslct = charIDToTypeID( "slct" );
    var desc258 = new ActionDescriptor();
    var idnull = charIDToTypeID( "null" );
        var ref148 = new ActionReference();
        var idLyr = charIDToTypeID( "Lyr " );
        ref148.putIndex( idLyr, layer.itemIndex );
    desc258.putReference( idnull, ref148 );
    executeAction( idslct, desc258, DialogModes.NO );
    return desc258;
  },
  getExportSelectedLayer = function(layer) {
    var path = activeDocument.path.fsName;
    try { 
      var desc = new ActionDescriptor(); 
      var ref = new ActionReference(); 
      ref.putEnumerated(stringIDToTypeID("layer"), stringIDToTypeID("ordinal"), stringIDToTypeID("targetEnum")); 
      desc.putReference(stringIDToTypeID("null"), ref); 
      desc.putString(stringIDToTypeID("fileType"), "png"); 
      desc.putInteger(stringIDToTypeID("quality"), 32); 
      desc.putInteger(stringIDToTypeID("metadata"), 0); 
      desc.putString(stringIDToTypeID("destFolder"), path); 
      desc.putBoolean(stringIDToTypeID("sRGB"), true); 
      desc.putBoolean(stringIDToTypeID("openWindow"), false); 
      executeAction(stringIDToTypeID("exportSelectionAsFileTypePressed"), desc, DialogModes.NO); 
      return path + '/' + layer.name;
    } catch (e) {
      return '';
    }
    return '';
  }
var layers = app.activeDocument.activeLayer.layers;
for (var i = 0; i < layers.length; i++) {
        var layer = layers[i];
        selectLayer(layer);
        getExportSelectedLayer(layer)
    }

```

Situation Two

```

createSnapshot = function(name) {
    var desc = new ActionDescriptor();
    var sref = new ActionReference();
    sref.putClass(charIDToTypeID("SnpS"));
    desc.putReference(charIDToTypeID("null"), sref);
    var fref = new ActionReference();
    fref.putProperty(charIDToTypeID("HstS"), charIDToTypeID("CrnH"));
    desc.putReference(charIDToTypeID("From"), fref);
    desc.putString(charIDToTypeID("Nm  "), name);
    executeAction(charIDToTypeID("Mk  "), desc, DialogModes.NO);
    return time;
  },
  resetPsd = function(name) {
    var doc = app.activeDocument;
    app.activeDocument.activeHistoryState = app.activeDocument.historyStates.getByName(name);
    app.activeDocument.save();
  }
createSnapshot('snap');
// do some export
resetPsd('snap')

```