code: function(formData, key, value) {
  		if (value==undefined) return;
  		// HACK: is it a FormData object? then use append
  		if (typeof(formData.append)==='function') {
  			formData.append(key, value);
  		} else {
  			formData[key] = value;
  		}
  	}
docs: Utility to set a key=value pair for FormData (a browser native object) or a normal data map.
  @param {FormData|Object} formData
  @param {String} key
  @param {*} value