C# 如何改变richtextbox中某个字符颜色

[kousansky]

c# winform richtextbox
给richtextbox一行一行的赋值,当某一行字符串中包含比如"good"时,就把这几个字母变成红色,不包含就不变色.
请问如何实现.
如下:
this is a dog.
what are you doing?
so good! thank you for your help.
good luck toyou.


---类似与上边这样

[烟波钓]

这个倒是没搞过 标记下

[wnyxy001]

            string[] str = { "this is a dog.", "what are you doing?", "so good! thank you for your help.", "good luck toyou." };
            foreach(string str0 in str)
            {
                if (str0.Contains("good"))
                {
                    int index=str0.IndexOf("good");
                    richTextBox1.SelectionColor = Color.Black;
                    richTextBox1.AppendText(str0.Substring(0,index));
                    richTextBox1.SelectionColor = Color.Red;
                    richTextBox1.AppendText("good");
                    richTextBox1.SelectionColor = Color.Black;
                    richTextBox1.AppendText(str0.Substring(index+4)+"\r\n");
                }
                else
                {
                    richTextBox1.SelectionColor = Color.Black;
                    richTextBox1.AppendText(str0+"\r\n");
                }

比较笨的方法

[wnyxy001]

            for (int i = 0; i < str.Length;i++ )
            {
                int lenth = richTextBox1.Text.Length;
                richTextBox1.AppendText(str[i]+"\r\n");
                if (richTextBox1.Lines[i].Contains("good"))
                {
                    richTextBox1.Select(lenth + richTextBox1.Lines[i].IndexOf("good"), 4);
                    richTextBox1.SelectionColor = Color.Red;
                }
            }

简单的方法

[Mm_loveYou]

private void 局部改变颜色ToolStripMenuItem_Click(object sender, EventArgs e)//局部改变字体的颜色
{
if (colorDialog1.ShowDialog() == DialogResult.OK)
{
richTextBox1.SelectionColor = colorDialog1.Color;
}
}
当然首先要添加colorDialog1，在工具箱->对话框。

[Mm_loveYou]

private void 局部改变颜色ToolStripMenuItem_Click(object sender, EventArgs e)//局部改变字体的颜色
  {
  if (colorDialog1.ShowDialog() == DialogResult.OK)
  {
  richTextBox1.SelectionColor = colorDialog1.Color;
  }
  }

当然首先要添加colorDialog1，在工具箱->对话框。