使用字体对话框更改字体 C#

Question

谁能告诉我如何使用字体对话框更改字体。我正在尝试获取它，以便选定的文本发生变化，或者如果没有选择文本，则仅更改标记后的字体（而不是整个文本框）。

这是我到目前为止所拥有的。谢谢

 private void menuFont_Click(object sender, EventArgs e)
    {
        if (fontDialog1.ShowDialog() == DialogResult.OK)
        {
            if (richtextbox.SelectedText != "")
            {
                richtextbox.Font = fontDialog1.Font;
            }
    }}

Answer 1

private void menuFont_Click(object sender, EventArgs e)
{
  if (fontDialog1.ShowDialog() == DialogResult.OK & !String.IsNullOrEmpty(richtextbox.Text))
  {
      richtextbox.SelectionFont = fontDialog1.Font;
  }
  else
  {
     //  richtextbox.SelectionFont = ?
  }
} 

---

编辑：

如果fontDialog1.ShowDialog() == DialogResult.OK为false，则可以使用&&根据 user210118 建议，仅此条件就满足 else 子句的使用

Answer 2

不是有 SelFont、SelX 将字体属性应用于所选文本吗？现在想来，也许是SelectedX，但应用程序是一样的。

Answer 3

使用 SelectionFont 属性RichTextBox，该示例将根据您的需要工作：

private void menuFont_Click(object sender, EventArgs e)
{
    if (fontDialog1.ShowDialog() == DialogResult.OK) {
        richtextbox.SelectionFont = fontDialog1.Font;
    }
}

Answer 4

要使输入的以下文本为不同的字体，而不仅仅是选定的文本，您需要向 RTB 添加运行块，然后写入其中。我为 RTB 实现了一个工具栏，其功能如下：

    public static void SetFontSize(RichTextBox target, double value)
    {
        // Make sure we have a richtextbox.
        if (target == null)
            return;

        // Make sure we have a selection. Should have one even if there is no text selected.
        if (target.Selection != null)
        {
            // Check whether there is text selected or just sitting at cursor
            if (target.Selection.IsEmpty)
            {
                // Check to see if we are at the start of the textbox and nothing has been added yet
                if (target.Selection.Start.Paragraph == null)
                {
                    // Add a new paragraph object to the richtextbox with the fontsize
                    Paragraph p = new Paragraph();
                    p.FontSize = value;
                    target.Document.Blocks.Add(p);
                }
                else
                {
                    // Get current position of cursor
                    TextPointer curCaret = target.CaretPosition;
                    // Get the current block object that the cursor is in
                    Block curBlock = target.Document.Blocks.Where
                        (x => x.ContentStart.CompareTo(curCaret) == -1 && x.ContentEnd.CompareTo(curCaret) == 1).FirstOrDefault();
                    if (curBlock != null)
                    {
                        Paragraph curParagraph = curBlock as Paragraph;
                        // Create a new run object with the fontsize, and add it to the current block
                        Run newRun = new Run();
                        newRun.FontSize = value;
                        curParagraph.Inlines.Add(newRun);
                        // Reset the cursor into the new block. 
                        // If we don't do this, the font size will default again when you start typing.
                        target.CaretPosition = newRun.ElementStart;
                    }
                }
            }
            else // There is selected text, so change the fontsize of the selection
            {
                TextRange selectionTextRange = new TextRange(target.Selection.Start, target.Selection.End);
                selectionTextRange.ApplyPropertyValue(TextElement.FontSizeProperty, value);
            }
        }
        // Reset the focus onto the richtextbox after selecting the font in a toolbar etc
        target.Focus();
    }