richTextBox设置选中的字体属性

public void ToggleBold()
{

if (richTextBox1.SelectionFont == null)
richTextBox1.SelectionFont = richTextBox1.Font;

FontStyle style = richTextBox1.SelectionFont.Style;

if (richTextBox1.SelectionFont.Bold)

style &= ~FontStyle.Bold;//恢复正常
else
style |= FontStyle.Bold;

richTextBox1.SelectionFont = new Font(richTextBox1.SelectionFont, style);
}

public void ToggleItalic()
{
if (richTextBox1.SelectionFont == null)
richTextBox1.SelectionFont = richTextBox1.Font;

FontStyle style = richTextBox1.SelectionFont.Style;

if (richTextBox1.SelectionFont.Italic)
style &= ~FontStyle.Italic;//恢复正常
else
style |= FontStyle.Italic;

richTextBox1.SelectionFont = new Font(richTextBox1.SelectionFont, style);
}

public void ToggleUnderLine()
{
if (richTextBox1.SelectionFont == null)
richTextBox1.SelectionFont = richTextBox1.Font;

FontStyle style = richTextBox1.SelectionFont.Style;

if (richTextBox1.SelectionFont.Underline)
style &= ~FontStyle.Underline;//恢复正常
else
style |= FontStyle.Underline;

richTextBox1.SelectionFont = new Font(richTextBox1.SelectionFont, style);
}