将gridpanel数据导入到Excel中

　　将coolite中gridpanel中的数据导入到本地excel中时，默认表格的表头不会随数据一起下载，下面就教你如何将表头随数据一起下载到本地excel中.

　　（1）store hidden gridpanel三种控件的配合使用 hidden的ID="hidAlarmHistory" gridpanel的ID="grdAlarmHistory",在head标签中加入以下js代码:

  var saveAlarmData = function() {
            hidAlarmHistory.setValue(Ext.encode(grdAlarmHistory.getRowsValues(false)));
        }

　　（2）在gridpanel中的每列<column>中必须加入:

<PrepareCommand Handler="" Args="grid,command,record,row,col,value" FormatHandler="False">
</PrepareCommand>

　　（3）选择模式必须加入<SelectionModel><ext:RowSelectionModel></ext:RowSelectionModel></SelectionModel>;

　　（4）按钮属性如下：AutoPostBack必须置为true;

<ext:Button ID="Button3" runat="server" Text="To Excel" OnClick="btnToExcel1" AutoPostBack="true" Icon="PageExcel">
      <Listeners>
           <Click Handler="saveAlarmData();" />
      </Listeners>
</ext:Button>

　　（5）代码如下：

　　

 public void ToExcel(GridPanel gp, string fileName, DataTable dt, HttpResponse resp)
   {
        resp.Clear();
        resp.ContentEncoding = System.Text.Encoding.GetEncoding("GB2312");
        resp.AppendHeader("Content-Disposition", "attachment;filename=" + fileName + ".xls");
        resp.ContentType = "application nd.ms-excel";

        string colHeaders = "", ls_item = "";
        int i = 0;
        int cl = gp.ColumnModel.Columns.Count - 1;
        string columns = "";

        //输出表头
        //取得数据表各列标题，各标题之间以t分割，最后一个列标题后加回车符 
        for (i = 0; i < cl; i++)
        {
            if (i == (cl - 1))//最后一列，加n
            {
                if (!gp.ColumnModel.Columns[i].Hidden)
                {
                    colHeaders += gp.ColumnModel.Columns[i].Header;
                    columns += gp.ColumnModel.Columns[i].DataIndex + ",";
                }
                colHeaders += "\n";
            }
            else
            {
                if (!gp.ColumnModel.Columns[i].Hidden && gp.ColumnModel.Columns[i].ColumnID != "update")
                {
                    colHeaders += gp.ColumnModel.Columns[i].Header + "\t";
                    columns += gp.ColumnModel.Columns[i].DataIndex + ",";
                }
            }
        }
        resp.Write(colHeaders);

        if (columns != "") columns = columns.Substring(0, columns.LastIndexOf(","));
        string[] columnall = columns.Split(',');

        cl = columnall.Length ;

        //逐行处理数据   
        for (int j = 0; j < dt.Rows.Count; j++)
        {
            //当前行数据写入HTTP输出流，并且置空ls_item以便下行数据     
            for (i = 0; i < cl; i++)
            {
                if (i == (cl - 1))
                {
                    ls_item += EditString(dt.Rows[j][columnall[i].ToString()].ToString()) + "\n";
                    
                }
                else
                {
                    ls_item += EditString(dt.Rows[j][columnall[i].ToString()].ToString()) + "\t";
                }
            }
            resp.Write(ls_item);
            ls_item = "";
        }
        Response.Flush();
        resp.End();
    }
    private static string EditString(string text1)//处理字符问题
    {

        
        if (text1.IndexOf('\r') != -1)
        {
            text1 = text1.Replace('\r', '');
        }
        if (text1.IndexOf('\n') != -1)
        {
            text1 = text1.Replace('\n', '');
        }
        if (text1.IndexOf('\t') != -1)
        {
            text1 = text1.Replace('\t', '');
        }
        if (text1.IndexOf("'") != -1)
        {
            text1 = text1.Replace("'", "");
        }
        if (text1.IndexOf("T") != -1)
        {
            text1 = text1.Replace("T", ""); 
        }

        if (text1.IndexOf(@"""") != -1)
        {
            text1 = text1.Replace(@"""", "");
        }
        return text1;


   }
    protected void btnToExcel1(object sender, EventArgs e)
     {
         string json = hidAlarmHistory.Value.ToString();
         bool addHeader = true;
         DataTable dt = new DataTable();
         StringBuilder sbstr = new StringBuilder();
         Dictionary<string, string>[] companies = JSON.Deserialize<Dictionary<string, string>[]>(json);
         foreach (Dictionary<string, string> row in companies)
         {

             if (addHeader)
             {
                 foreach (KeyValuePair<string, string> keyValuePair in row)
                 {
                     dt.Columns.Add(keyValuePair.Key);
                 }
             }
             addHeader = false;
             ArrayList list = new ArrayList();
             DataRow dr = dt.NewRow();
             foreach (KeyValuePair<string, string> keyValuePair in row)
             {

                 dr[keyValuePair.Key] = keyValuePair.Value;
                 if (dr["ah_id"] == dr[keyValuePair.Key])
                 {
                     sbstr.Append(keyValuePair.Value + ";");
                 }
             }
             dt.Rows.Add(dr);
         }
         ToExcel(grdAlarmHistory,"date",dt, this.Response);
     }