TextBoxBase.TextLength 属性

定义

获取控件中文本的长度。Gets the length of text in the control.

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

属性值

Int32

控件文本中所含的字符数。The number of characters contained in the text of the control.

属性

示例

下面的代码示例演示如何使用 AppendText 方法和 TextLength 属性将文本从一个复制 TextBox 到另一个。The following code example demonstrates how to use the AppendText method and the TextLength property to copy text from one TextBox to another. 此示例要求 TextBox 在窗体中添加了名为和的两个控件, textBox1 并将文本分配给了 textBox2 textBox1Text 属性。This example requires that two TextBox controls named, textBox1 and textBox2, have been added to a form and that textBox1 has text assigned to its Text property.

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

注解

您可以使用此属性来确定字符串中的字符数(如搜索控件文本内的特定文本字符串,其中需要了解字符的总数)。You can use this property to determine the number of characters in a string for tasks such as searching for specific strings of text within the text of the control, where knowledge of the total number of characters is needed.

适用于

另请参阅