驗證的文本框的標籤頁

Question

這裏是我的情況：我有一個TabControl三個TabPage的（tabPage1 & tabPage2 & tabPage3）。在每一頁我有一個8 - 10 textbox。我如何爲textbox, combobox, datetimepicker - 在Windows窗體應用程序中進行驗證？

這是我的表單應用程序

Answer 1

您可以使用Control的Validating事件與ErrorProvider。

我創建了一個示例應用程序。

它有2頁的選項卡控件：

• TabPage1
  • TextBox2中
  • textbox3
  • textbox4
  • textbox5
  • combobox1
  • combobox2
  • combobox3
  • datetimepicker1
• TabPage2
  • TextBox1中

從工具箱添加ErrorProvider控制到form。

在form的構造，訂閱驗證事件的所有控件：

textBox1.Validating += textBox_Validating; 
textBox2.Validating += textBox_Validating; 
textBox3.Validating += textBox_Validating; 
textBox4.Validating += textBox_Validating; 
textBox5.Validating += textBox_Validating; 

comboBox1.Validating += comboBox_Validating; 
comboBox2.Validating += comboBox_Validating; 
comboBox3.Validating += comboBox_Validating; 

dateTimePicker1.Validating += dateTimePicker1_Validating; 

下面是檢查空值的事件：

bool IsValidated = true; //will be checked on button click 
void dateTimePicker1_Validating(object sender, CancelEventArgs e) 
{ 
    DateTimePicker datetimepicker = sender as DateTimePicker; 
    if (datetimepicker.Value == null) 
    { 
     errorProvider1.SetError(datetimepicker, "Required"); 
     IsValidated = false; 
    } 
} 

void comboBox_Validating(object sender, CancelEventArgs e) 
{ 
    ComboBox combo = sender as ComboBox; 
    if(combo.SelectedIndex == -1) 
    { 
     errorProvider1.SetError(combo, "Required"); 
     IsValidated = false; 
    } 
} 

void textBox_Validating(object sender, CancelEventArgs e) 
{ 
    TextBox txtbox = sender as TextBox; 
    if (txtbox.Text == "" || txtbox.Text.Length > 2) 
    { 
     errorProvider1.SetError(txtbox, "Required"); 
     IsValidated = false; 
    } 
} 

Validating事件觸發，當你從失去焦點任何控制，但如果有人直接點擊Submit按鈕怎麼辦？

爲了解決這個問題，你也可以驗證所有的控制按鈕點擊所有選項卡：

private void btnSubmit_Click(object sender, EventArgs e) 
{ 
    //traverse all Tab Pages 
    foreach (TabPage tabpage in tabControl1.Controls.OfType<TabPage>()) 
    { 
     foreach (TextBox txtbox in tabpage.Controls.OfType<TextBox>()) 
      textBox_Validating(txtbox, null); 

     foreach (ComboBox combo in tabpage.Controls.OfType<ComboBox>()) 
      comboBox_Validating(combo, null); 

     foreach (DateTimePicker date in tabpage.Controls.OfType<DateTimePicker>()) 
      dateTimePicker1_Validating(date, null); 
    } 

    if (IsValidated) 
     MessageBox.Show("submitted"); 
    else 
     MessageBox.Show("not submitted"); 
} 

它會顯示對每個控制誤差（見以下快照）並不會提交表單。