技术开发 频道

扩展GridView控件-导出为Excel

【IT168 技术文档】扩展GridView控件(八)——导出为Excel

作者:webabcd


介绍
把GridView导出为一个Excel文件算是一个经常要用到的功能,也比较简单,我们来扩展一个GridView以实现这样的功能。


控件开发
1、新建一个继承自GridView的类。
/// <summary>
/// 继承自GridView
/// </summary>

[ToolboxData(@"<{0}:SmartGridView runat='server'></{0}:SmartGridView>")]
public class SmartGridView : GridView
{
}

2、重写OnRowCommand,以实现把GridView导出为Excel的功能
        /// <summary>
        
/// OnRowCommand
        
/// </summary>
        
/// <param name="e"></param>

        protected override void OnRowCommand(GridViewCommandEventArgs e)
        
{
            
if (e.CommandName.ToLower() == "exporttoexcel")
            
{
                System.Web.HttpContext.Current.Response.ClearContent();
                
// e.CommandArgument用“;”隔开两部分,左边的部分为导出Excel的文件名称
                System.Web.HttpContext.Current.Response.AddHeader("content-disposition""attachment; filename=" + e.CommandArgument.ToString().Split(';')[0+ ".xls");
                System.Web.HttpContext.Current.Response.ContentType 
= "application/excel";

                System.IO.StringWriter sw 
= new System.IO.StringWriter();
                HtmlTextWriter htw 
= new HtmlTextWriter(sw);

                
// e.CommandArgument用“;”隔开两部分,右边的部分为需要隐藏的列的索引(列索引用“,”分开)
                if (e.CommandArgument.ToString().Split(';').Length > 1)
                
{
                    
foreach (string s in e.CommandArgument.ToString().Split(';')[1].Split(','))
                    
{
                        
int i;

                        
if (!Int32.TryParse(s, out i))
                        
{
                            
throw new ArgumentException("需要隐藏的列的索引不是整数"); 
                        }


                        
if (i > this.Columns.Count)
                        
{
                            
throw new ArgumentOutOfRangeException("需要隐藏的列的索引超出范围");
                        }


                        
this.Columns[i].Visible = false;
                    }

                }


                
// 隐藏“导出Excel”按钮
                ((Control)e.CommandSource).Visible = false;

                
// 如果HeaderRow里的控件是button的话,则把它替换成文本
                foreach (TableCell tc in this.HeaderRow.Cells)
                
{
                    
// TableCell里的每个Control
                    foreach (Control c in tc.Controls)
                    
{
                        
// 如果控件继承自接口IButtonControl
                        if (c.GetType().GetInterface("IButtonControl"!= null && c.GetType().GetInterface("IButtonControl").Equals(typeof(IButtonControl)))
                        
{
                            
// 如果该控件不是“导出Excel”按钮则把button转换成文本
                            if (!c.Equals(e.CommandSource))
                            
{
                                tc.Controls.Clear();
                                tc.Text 
= ((IButtonControl)c).Text;
                            }

                        }

                    }

                }


                
// 将服务器控件的内容输出到所提供的 System.Web.UI.HtmlTextWriter 对象中
                this.RenderControl(htw);

                System.Web.HttpContext.Current.Response.Write(sw.ToString());
                System.Web.HttpContext.Current.Response.End();
            }


            
base.OnRowCommand(e);
        }



0
相关文章