TextBoxBase.TextLength 屬性

定義

取得控制項中文字的長度。

public:
 virtual property int TextLength { int get(); };
[System.ComponentModel.Browsable(false)]
public virtual int TextLength { get; }
[<System.ComponentModel.Browsable(false)>]
member this.TextLength : int
Public Overridable ReadOnly Property TextLength As Integer

屬性值

包含在控制項文字中的字元數目。

屬性

範例

下列程式碼範例示範如何使用 AppendText 方法和 TextLength 屬性,將文字從一個複製到另一個 TextBox 。 本範例要求已將名為 textBox1 和 的兩 TextBox 個控制項新增至表單, textBox1 且已將文字指派給其 TexttextBox2 屬性。

void AppendTextBox1Text()
{
   // Determine if text is selected in textBox1.
   if ( textBox1->SelectionLength == 0 )

   // No selection made, return.
   return;

   // Determine if the text being appended to textBox2 exceeds the MaxLength property.
   if ( (textBox1->SelectedText->Length + textBox2->TextLength) > textBox2->MaxLength )
         MessageBox::Show( "The text to paste in is larger than the maximum number of characters allowed" ); // Append the text from textBox1 into textBox2.
   else
         textBox2->AppendText( textBox1->SelectedText );
}
private void AppendTextBox1Text()
{
   // Determine if text is selected in textBox1.
   if(textBox1.SelectionLength == 0)
      // No selection made, return.
      return;
   
   // Determine if the text being appended to textBox2 exceeds the MaxLength property.
   if((textBox1.SelectedText.Length + textBox2.TextLength) > textBox2.MaxLength)
      MessageBox.Show("The text to paste in is larger than the maximum number of characters allowed");
   else
      // Append the text from textBox1 into textBox2.
      textBox2.AppendText(textBox1.SelectedText);
}
Private Sub AppendTextBox1Text()
   ' Determine if text is selected in textBox1.
   If textBox1.SelectionLength = 0 Then
      ' No selection made, return.
      Return
   End If
   ' Determine if the text being appended to textBox2 exceeds the MaxLength property.
   If textBox1.SelectedText.Length + textBox2.TextLength > textBox2.MaxLength Then
      MessageBox.Show("The text to paste in is larger than the maximum number of characters allowed")
      ' Append the text from textBox1 into textBox2.
   Else
      textBox2.AppendText(textBox1.SelectedText)
   End If
End Sub

備註

您可以使用這個屬性來判斷字串中的字元數目,例如在控制項文字中搜尋特定文字字串,其中需要字元總數的知識。

適用於

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