無法清除文本框

Question

我想清除所有文本框。寫的公共職能爲：

public void clean(Control parent) 
{ 
    try 
    { 
     foreach (Control c in parent.Controls) 
     { 
      TextBox tb = c as TextBox; //if the control is a textbox 
      if (tb != null)//Will be null if c is not a TextBox 
      { 
       tb.Text = String.Empty;//display nothing 
      } 
     } 
    } 
    catch (Exception ex) 
    { 
     Console.WriteLine("{0} Exception caught.", ex); 
    } 
} 

在類頁面

我希望它被稱爲我宣佈：

PublicFunctions pubvar = new PublicFunctions(); 

，我把它作爲

pubvar.clean(Page); 

，但它不是工作......甚至沒有發生錯誤...我的文本框不清除...幫助？

Answer 1

您應該使用遞歸循環來檢查所有控件。

試試這個代碼

using System; 
using System.Collections.Generic; 
using System.Web.UI; 
using System.Web.UI.WebControls; 

public class PublicFunctions 
{ 
    public void Clean(Control parent) 
    { 
     var controls = GetAllControls(parent); 

     foreach (Control c in controls) 
     { 
      TextBox tb = c as TextBox; 
      if (tb != null) 
      { 
       tb.Text = String.Empty; 
      } 
     } 
    } 

    public IEnumerable<Control> GetAllControls(Control parent) 
    { 
     foreach (Control control in parent.Controls) 
     { 
      yield return control; 

      foreach (Control innerControl in control.Controls) 
      { 
       yield return innerControl; 
      } 
     } 
    } 
}