使用ADO.net将数据导出到Excel并提供下载

来源：aspcool 作者：出处：巧巧读书 2006-04-18 进入讨论组

关键词：
ado.net
excel

public string DataTableToExcel(DataTable dt,string excelPath) 
{ 
if(dt == null) 
{ 
return "DataTable不能为空"; 
} 

int rows = dt.Rows.Count; 
int cols = dt.Columns.Count; 
StringBuilder sb; 
string connString; 

if(rows == 0) 
{ 
return "没有数据"; 
} 

sb = new StringBuilder(); 
connString = string.Format(ConnectionString,excelPath); 

//生成创建表的脚本 
sb.Append("CREATE TABLE "); 
sb.Append(dt.TableName + " ( "); 

for(int i=0;i { 
if(i < cols - 1) 
sb.Append(string.Format("{0} varchar,",dt.Columns[i].ColumnName)); 
else 
sb.Append(string.Format("{0} varchar)",dt.Columns[i].ColumnName)); 
} 

using(OleDbConnection objConn = new OleDbConnection(connString)) 
{ 
OleDbCommand objCmd = new OleDbCommand(); 
objCmd.Connection = objConn; 

objCmd.CommandText = sb.ToString(); 

try 
{ 
objConn.Open(); 
objCmd.ExecuteNonQuery(); 
} 
catch(Exception e) 
{ 
return "在Excel中创建表失败，错误信息：" + e.Message; 
} 

生成插入数据脚本#region 生成插入数据脚本 
sb.Remove(0,sb.Length); 
sb.Append("INSERT INTO "); 
sb.Append(dt.TableName + " ( "); 

for(int i=0;i { 
if(i < cols - 1) 
sb.Append(dt.Columns[i].ColumnName + ","); 
else 
sb.Append(dt.Columns[i].ColumnName + ") values ("); 
} 

for(int i=0;i { 
if(i < cols - 1) 
sb.Append("@" + dt.Columns[i].ColumnName + ","); 
else 
sb.Append("@" + dt.Columns[i].ColumnName + ")"); 
} 
#endregion 


//建立插入动作的Command 
objCmd.CommandText = sb.ToString(); 
OleDbParameterCollection param = objCmd.Parameters; 

for(int i=0;i { 
param.Add(new OleDbParameter("@" + dt.Columns[i].ColumnName, OleDbType.VarChar)); 
} 

//遍历DataTable将数据插入新建的Excel文件中 
foreach (DataRow row in dt.Rows) 
{ 
for (int i=0; i { 
param[i].Value = row[i]; 
} 

objCmd.ExecuteNonQuery(); 
} 

return "数据已成功导入Excel"; 
}//end using 
}