手把手教你如何扩展GridView之自带Excel和Word导出

在web应用程序中，我们是不是很发愁打印问题，您是不是有过为了打印写Activex的经历，我们有没有想过，Word和Excel的打印功能能被我们利用起来呢?只要我们将我们将数据导出到Excel或者Word中，打印岂不是小case了么。下面就谈谈如何让GridView自己支持导出Excel和Word 。
首先增加了两个属性，用于指示是否支持Excel导出和Word导出


//增加了一个设置是否显示“导出Word”按钮的属性




/**//**//**//// <summary>


/// 排序提示信息


/// </summary>


[


Description("显示导出到Word"),


Category("扩展"),


DefaultValue(true)


]


public virtual bool ShowExportWord




...{


get




...{


object obj2 = this.ViewState["ShowExportWord"];


if (obj2 != null)




...{


return (bool)obj2;


}


return true;


}


set




...{


bool aShowExportWord = this.ShowExportWord;


if (value != aShowExportWord)




...{


this.ViewState["ShowExportWord"] = value;


if (base.Initialized)




...{


base.RequiresDataBinding = true;


}


}


}


}


//增加了一个设置是否显示“导出Excel”按钮的属性


[


Description("显示导出到Excel"),


Category("扩展"),


DefaultValue(true)


]


public virtual bool ShowExportExcel




...{


get




...{


object obj2 = this.ViewState["ShowExportExcel"];


if (obj2 != null)




...{


return (bool)obj2;


}


return true;


}


set




...{


bool aShowExportExcel = this.ShowExportExcel;


if (value != aShowExportExcel)




...{


this.ViewState["ShowExportExcel"] = value;


if (base.Initialized)




...{


base.RequiresDataBinding = true;


}


}


}


}



声明两个LinkButton控件btnExportWord,btnExport，分别用于点击导出Excel和点击导出word,并在控件的OnInit事件中初始化两个控件
声明两个LinkButton,并在控件的OnInit中初始化






LinkButton btnExportWord;


LinkButton btnExport; protected override void OnInit(EventArgs e)




...{


this.EnableViewState = true;




btnExport = new LinkButton();


btnExport.CommandName = "ExportToExcel";


btnExport.EnableViewState = true;


btnExport.Text = "导出Excel";


btnExportWord = new LinkButton();


btnExportWord.CommandName = "ExportToWord";


btnExportWord.EnableViewState = true;


btnExportWord.Text = "导出Word";


base.OnInit(e);


}





将两个LinkButton添加到GridView子控件中








protected override int CreateChildControls(System.Collections.IEnumerable dataSource, bool dataBinding) ...{


int res = base.CreateChildControls(dataSource, dataBinding);


try




...{


GridViewRow row = new GridViewRow(0, 0, DataControlRowType.Pager, DataControlRowState.Normal); TableCell cell2 = new TableCell();


cell2.HorizontalAlign = HorizontalAlign.Right;


cell2.Wrap = false; if (this.ShowExportExcel == true)




...{


l1 = new Literal();


l1.Text = " [";


cell2.Controls.Add(l1);


cell2.Controls.Add(btnExport);


l1 = new Literal();


l1.Text = "] ";


cell2.Controls.Add(l1);


}


if (this.ShowExportWord == true)




...{


l1 = new Literal();


l1.Text = " [";


cell2.Controls.Add(l1);


cell2.Controls.Add(btnExportWord);


l1 = new Literal();


l1.Text = "] ";


cell2.Controls.Add(l1);


} r.Cells.Add(cell2);


this.Controls[0].Controls.AddAt(0, row);


}


catch




...{


}


}


return res;


}





在导出的时候，我们希望一些列不被导出，如修改，删除这样的列，因此我们添加了这样的一个属性
用于指定不被导出列，列名之间用,隔开






string _UnExportedColumnNames = "";


[


Description("不导出的数据列集合,将HeaderText用,隔开"),


Category("扩展"),


DesignerSerializationVisibility(DesignerSerializationVisibility.Content),


PersistenceMode(PersistenceMode.InnerProperty)


]


public string UnExportedColumnNames




...{


get




...{


return _UnExportedColumnNames;


}


set




...{


_UnExportedColumnNames = value;


}


}





在导出的时候，原来的GridView列表中会有一些LinkButton或者DropDownList控件，导出的时候，我们也希望将其换成纯文本，用下面这个函数可以完成这个目的
用于将GridView中的LinkButton和DropDownList转换成文本的方法






private void DisableControls(Control gv)




...{


LinkButton lb = new LinkButton();


Literal l = new Literal();


string name = String.Empty;


for (int i = 0; i < gv.Controls.Count; i++)




...{


if (gv.Controls[i].GetType() == typeof(LinkButton))




...{


l.Text = (gv.Controls[i] as LinkButton).Text;


gv.Controls.Remove(gv.Controls[i]);


gv.Controls.AddAt(i, l);


}


else if (gv.Controls[i].GetType() == typeof(DropDownList))




...{


l.Text = (gv.Controls[i] as DropDownList).SelectedItem.Text;


gv.Controls.Remove(gv.Controls[i]);


gv.Controls.AddAt(i, l);


}


if (gv.Controls[i].HasControls())




...{


DisableControls(gv.Controls[i]);


}


}


}



下面是处理ItemCommand，将GridView导出的代码
处理OnRowCommand事件，将GridView数据导出到Excel和Word




protected override void OnRowCommand(GridViewCommandEventArgs e)




...{


base.OnRowCommand(e);


if (e.CommandName == "ExportToExcel")




...{


string[] ss = UnExportedColumnNames.Split(',');


System.Collections.Generic.List<string> list = new System.Collections.Generic.List<string>();


foreach (string s in ss)




...{


if (s != ",")




...{


list.Add(s);


}


}


ShowToolBar = false;


this.AllowSorting = false;


HttpContext.Current.Response.Clear();


HttpContext.Current.Response.AddHeader("content-disposition",


"attachment;filename=" + ExcelFileName + ".xls");


HttpContext.Current.Response.Charset = "GB2312";


HttpContext.Current.Response.ContentEncoding = System.Text.Encoding.GetEncoding("GB2312");//设置输出流为简体中文


HttpContext.Current.Response.ContentType = "application/ms-excel";




System.IO.StringWriter stringWrite = new System.IO.StringWriter();


System.Web.UI.HtmlTextWriter htmlWrite =


new HtmlTextWriter(stringWrite);


bool showCheckAll = ShowCheckAll;


this.ShowCheckAll = false;


this.AllowPaging = false;


OnBind();


DisableControls(this);


foreach (DataControlField c in this.Columns)




...{


if (list.Contains(c.HeaderText) && !string.IsNullOrEmpty(c.HeaderText))




...{


c.Visible = false;


}


}


this.RenderControl(htmlWrite);


string content = System.Text.RegularExpressions.Regex.Replace(stringWrite.ToString(), "(<a[^>]+>)|(</a>)", "");


HttpContext.Current.Response.Write(content);


HttpContext.Current.Response.End();


this.AllowPaging = true;


this.AllowSorting = true;


ShowToolBar = true;


this.ShowCheckAll = showCheckAll;


OnBind();


}


else if (e.CommandName == "ExportToWord")




...{


string[] ss = UnExportedColumnNames.Split(',');


System.Collections.Generic.List<string> list = new System.Collections.Generic.List<string>();


foreach (string s in ss)




...{


if (s != ",")




...{


list.Add(s);


}


}


ShowToolBar = false;


this.AllowSorting = false;


HttpContext.Current.Response.Clear();


HttpContext.Current.Response.AddHeader("content-disposition",


"attachment;filename=" + ExcelFileName + ".doc");


HttpContext.Current.Response.Charset = "GB2312";


HttpContext.Current.Response.ContentEncoding = System.Text.Encoding.GetEncoding("GB2312");//设置输出流为简体中文


HttpContext.Current.Response.ContentType = "application/ms-word";




System.IO.StringWriter stringWrite = new System.IO.StringWriter();


System.Web.UI.HtmlTextWriter htmlWrite =


new HtmlTextWriter(stringWrite);


bool showCheckAll = ShowCheckAll;


this.ShowCheckAll = false;


this.AllowPaging = false;


OnBind();


DisableControls(this);


foreach (DataControlField c in this.Columns)




...{


if (list.Contains(c.HeaderText) && !string.IsNullOrEmpty(c.HeaderText))




...{


c.Visible = false;


}


}


this.RenderControl(htmlWrite);


string content = System.Text.RegularExpressions.Regex.Replace(stringWrite.ToString(), "(<a[^>]+>)|(</a>)", "");


HttpContext.Current.Response.Write(content);


HttpContext.Current.Response.End();


this.AllowPaging = true;


this.AllowSorting = true;


ShowToolBar = true;


ShowCheckAll = showCheckAll;


OnBind();


}


}





使用的时候，只要指定ShowExportExcel=True，ShowExportWord=True就自动出现导出Word和导出Excel的按钮了，点击自动会将GridView中的数据导出到Word或者Excel中了，如果原GridView是多页的，那也会自动将全部数据（而不是当前页的数据）导出，而且会剔除原来数据中的一些超级链接。使用起来相当简单，效果页非常好。