Flex 带导入导出Excel的DataGrid

原文网址：http://nlslzf.iteye.com/blog/228038
 package  com.yyhy.flex.util
 {
     import  flash.events.KeyboardEvent;
     import  flash.events.TextEvent;
     import  flash.text.TextField;
     import  flash.text.TextFieldType;

     import  mx.controls.*;
     import  mx.controls.dataGridClasses.DataGridColumn;
     //import mx.events.
     public   class  EIDataGrid  extends  DataGrid
     {
         public  function EIDataGrid()
         {
             super ();
             this .addEventListener(KeyboardEvent.KEY_DOWN,KeyDownHandler);
             this .addEventListener(KeyboardEvent.KEY_UP,KeyUpHandler);
         }
         private  function KeyDownHandler(event:KeyboardEvent): void
             {
                 if  (event.ctrlKey && ! this .getChildByName( "clipboardProxy" ))
                 {
                     // Add an invisible TextField object to the DataGrid
                     var textField:TextField = new  TextField();
                     textField.name = "clipboardProxy" ;
                     this .addChild(textField);
                     textField.visible = false ;

                     textField.type = TextFieldType.INPUT;
                     textField.multiline = true ;

                     // Populate the TextField with selected data in TSV format

                     textField.text = getTextFromItems(this .selectedItems);
                     //textField.text = getTextFromItems(dataGrid.dataProvider.source);
                     textField.setSelection(0 , textField.text.length -  1 );

                     // Listen for textInput event

                     textField.addEventListener(TextEvent.TEXT_INPUT,
                     clipboardProxyPasteHandler);

                     // Set player-level focus to the TextField

                     systemManager.stage.focus = textField;
                 }//end if
             }//end function


             private  function KeyUpHandler(event:KeyboardEvent): void
             {
                 if  (!event.ctrlKey)
                 {
                     var textField:TextField = TextField(this .getChildByName( "clipboardProxy" ));
                     if  (textField)
                     {
                         this .removeChild(textField);
                     }//end if
                 }//end if
             }//end function

             private  function clipboardProxyPasteHandler(event:TextEvent): void
             {
                 // Extract values from TSV format and populate the DataGrid

                 var items:Array = getItemsFromText(event.text);
                 for  each (var item:Object in items)
                     this .dataProvider.addItem(item);
             }//end function

             private  function getItemsFromText(text:String):Array
             {
                 var rows:Array = text.split("\n" );
                 if  (!rows[rows.length -  1 ])
                     rows.pop();

                 var columns:Array = this .columns;
                 var itemsFromText:Array = [];

                 for  each (var rw:String in rows)
                 {
                     var fields:Array = rw.split("\t" );

                     var n:int  = Math.min(columns.length, fields.length);
                     var item:Object = {};
                     for  (var i: int  =  0 ; i < n; i++)
                         item[columns[i].dataField] = fields[i];
                     itemsFromText.push(item);
                  }

                 return  itemsFromText;
             }//end function
         private  function getTextFromItems(items:Array):String
             {
                 var columns:Array = this .columns;
                 var textFromItems:String = "" ;
                 //add datagrid headtext
                 for  each (var i: DataGridColumn in columns)
                 {
                     textFromItems += i.headerText + "\t" ;
                 }
                 textFromItems += "\n" ;

                 for  each (var it:Object in items)
                 {

                     for  each (var c: DataGridColumn in columns)
                         textFromItems += it[c.dataField] + "\t" ;
                     textFromItems += "\n" ;
                 }

                 return  textFromItems;
             }//end function
     }
 }