1.普通页面遍历TextBox控件清空的方法，其他控件类似

foreach(Control c in this.controls)
{
  if(c is TextBox)
	{
           TextBox tb=(TextBox)c；
		tb.Text=String.empty；	
	}
}
//或
foreach (Control col in this.Controls)   
{   
     if (col.GetType().Name.Equals("TextBox"))   
     {   
         ((TextBox)col).Text = String.empty； 
     }   
}  

//不含母板页
foreach (System.Web.UI.Control txtobj in this.Page.Controls)

{ 
    if (txtobj.GetType().Name .Equals("TextBox")) 
    { 
       // ((TextBox)txtobj).Text = String.Empty;//这是第一种方法赋值，第二种在下面 
        TextBox tb = new TextBox(); 
         tb = (TextBox)this.FindControl(txtobj.ID); 

         tb.Text = String.Empty; 
    } 
}

//套用母版页的页面遍历TextBox控件的方法，其他控件类似

foreach (Control cp in Page.Controls)    
{    
       foreach (System.Web.UI.Control ct in cp.Controls)    
       {   
            if (ct is HtmlForm)    
            {    
                  foreach (Control con in ct.Controls)   
                  {    
                      foreach (Control c in con.Controls)   
                      {   
                          if (c is TextBox)   
                          {   
                              (c as TextBox).Text = String.Empty;   
                          }   
                      }    
                  }    
             }    
       }    
}  

// 清空指定页面上所有的控件内容
//public static void ClearAllContent() 
//清空指定页面上所有的控件内容
//包括TextBox，CheckBox,CheckBoxList,RadioButton,RadioButtonList。不过不清 
//除如ListBox，DropDownList，因为这样的控件值对当前页面来说还能用，一般这些控件里都是保存的字典数据。  
//<param name="page"> 指定的页面</param> 
public static void ClearAllContent(System.Web.UI.Control page) 
{ 
int nPageControls = page.Controls.Count; 
for (int i = 0; i < nPageControls; i++) 
{ 
foreach (System.Web.UI.Control control in page.Controls[i].Controls) 
{ 
if (control.HasControls()) 
{ 
ClearAllText(control); 
} 
else 
{ 
if (control is TextBox) 
(control as TextBox).Text = ""; 

if (control is CheckBox) 
(control as CheckBox).Checked = false; 

if (control is RadioButtonList) 
(control as RadioButtonList).SelectedIndex = -1; 

if (control is RadioButton) 
(control as RadioButton).Checked = false; 

if (control is CheckBoxList) 
{ 
foreach (ListItem item in (control as CheckBoxList).Items) 
{ 
item.Selected = false; 
} 
} 
}//if..else 
}//foreach 
}//for 
}