如何在RichTextBox中删除特定的文本行?
另一个解决方案:
private void DeleteLine(int a_line)
{
int start_index = richTextBox.GetFirstCharIndexFromLine(a_line);
int count = richTextBox.Lines[a_line].Length;
// Eat new line chars
if (a_line < richTextBox.Lines.Length - 1)
{
count += richTextBox.GetFirstCharIndexFromLine(a_line + 1) -
((start_index + count - 1) + 1);
}
richTextBox.Text = richTextBox.Text.Remove(start_index, count);
}
richTextBox.SelectionStart = richTextBox.GetFirstCharIndexFromLine(your_line);
richTextBox.SelectionLength = this.richTextBox.Lines[your_line].Length+1;
this.richTextBox.SelectedText = String.Empty;
试试这个:
Dim lst As New ListBox
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Me.Controls.Add(lst)
For Each cosa As String In Me.RichTextBox1.Lines
lst.Items.Add(cosa)
Next
lst.Items.RemoveAt(2) 'the integer value must be the line that you want to remove -1
Me.RichTextBox1.Text = String.Empty
For i As Integer = 0 To lst.Items.Count - 1
If Me.RichTextBox1.Text = String.Empty Then
Me.RichTextBox1.Text = lst.Items.Item(i)
Else
MeMe.RichTextBox1.Text = Me.RichTextBox1.Text & Environment.NewLine & lst.Items.Item(i).ToString
End If
Next
End Sub
http://social.msdn.microsoft.com/Forums/en-US/vbgeneral/thread/63647481-743d-4e55-9043-e0db5106a03a/
我不知道是否有一种简单的方法可以一步完成。您可以使用富文本框的.Text属性上的.Split函数来获取行数组。
string[] lines = richTextBox1.Text.Split( "\n".ToCharArray() )
然后编写一些代码将数组重新组装成单个文本字符串,删除所需的行,并将其复制回富文本框的.Text属性中。
这里有一个简单的示例:
string[] lines = richTextBox1.Text.Split("\n".ToCharArray() );
int lineToDelete = 2; //O-based line number
string richText = string.Empty;
for ( int x = 0 ; x < lines.GetLength( 0 ) ; x++ )
{
if ( x != lineToDelete )
{
richText += lines[ x ];
richText += Environment.NewLine;
}
}
richTextBox1.Text = richText;
基于tomanu的解决方案,但没有额外开销
int start_index = LogBox.GetFirstCharIndexFromLine(linescount);
int count = LogBox.GetFirstCharIndexFromLine(linescount + 1) - start_index;
LogBox.Text = LogBox.Text.Remove(start_index, count);
int count = richTextBox.Lines[a_line].Length;
这一行。 - Dave Cousineauint LineToDelete = 50;
List<string> lines = richTextBox1.Lines.ToList();
lines.Remove(LineToDelete);
richTextBox1.Lines = lines.ToArray();
有很多好的答案,但我发现许多都太复杂了。
string[] LinesArray = this.richTextBox1.Lines;
this.richTextBox1.Clear();
for (int line = 0; line < LinesArray.Length; line++)
{
if (!LinesArray[line].Contains("< Test Text To Remove >"))
{
this.richTextBox1.AppendText(LinesArray[line] + Environment.NewLine);
}
}
这是我的单元测试实现。
public static void DeleteLine([NotNull] this RichTextBox pRichTextBox, int pLineIndex) {
if (pLineIndex < 0 || pLineIndex >= pRichTextBox.Lines.Length)
throw new InvalidOperationException("There is no such line.");
var start = pRichTextBox.GetFirstCharIndexFromLine(pLineIndex);
var isLastLine = pLineIndex == pRichTextBox.Lines.Length - 1;
var nextLineIndex = pLineIndex + 1;
var end = isLastLine
? pRichTextBox.Text.Length - 1
: pRichTextBox.GetFirstCharIndexFromLine(nextLineIndex) - 1;
var length = end - start + 1;
pRichTextBox.Text = pRichTextBox.Text.Remove(start, length);
}
单元测试:
(使用\n
而不是Environment.NewLine
,因为至少对于我来说,RTB会自动将\r\n
替换为\n
)
[TestMethod]
public void TestDeleteLine_SingleLine() {
var rtb = new RichTextBox();
rtb.Text = "This is line1.\n";
rtb.DeleteLine(0);
var expected = "";
Assert.AreEqual(expected, rtb.Text);
}
[TestMethod]
public void TestDeleteLine_BlankLastLine() {
var rtb = new RichTextBox();
rtb.Text = "\n";
rtb.DeleteLine(1);
var expected = "\n";
Assert.AreEqual(expected, rtb.Text);
}
[TestMethod]
public void TestDeleteLine_SingleLineNoEOL() {
var rtb = new RichTextBox();
rtb.Text = "This is line1.";
rtb.DeleteLine(0);
var expected = "";
Assert.AreEqual(expected, rtb.Text);
}
[TestMethod]
public void TestDeleteLine_FirstLine() {
var rtb = new RichTextBox();
rtb.Text = "This is line1.\nThis is line2.\nThis is line3.";
rtb.DeleteLine(0);
var expected = "This is line2.\nThis is line3.";
Assert.AreEqual(expected, rtb.Text);
}
[TestMethod]
public void TestDeleteLine_MiddleLine() {
var rtb = new RichTextBox();
rtb.Text = "This is line1.\nThis is line2.\nThis is line3.";
rtb.DeleteLine(1);
var expected = "This is line1.\nThis is line3.";
Assert.AreEqual(expected, rtb.Text);
}
[TestMethod]
public void TestDeleteLine_LastLine() {
var rtb = new RichTextBox();
rtb.Text = "This is line1.\nThis is line2.\nThis is line3.";
rtb.DeleteLine(2);
var expected = "This is line1.\nThis is line2.\n";
Assert.AreEqual(expected, rtb.Text);
}
[TestMethod]
public void TestDeleteLine_OneBlankLine() {
var rtb = new RichTextBox();
rtb.Text = "\n";
rtb.DeleteLine(0);
var expected = "";
Assert.AreEqual(expected, rtb.Text);
}
[TestMethod]
public void TestDeleteLine_BlankLines() {
var rtb = new RichTextBox();
rtb.Text = "\n\n\n\n\n";
rtb.DeleteLine(2);
var expected = "\n\n\n\n";
Assert.AreEqual(expected, rtb.Text);
}
[TestMethod, ExpectedException(typeof(InvalidOperationException))]
public void TestDeleteLine_Exception_BeforeFront() {
var rtb = new RichTextBox();
rtb.Text = "\n\n\n\n\n";
rtb.DeleteLine(-1);
}
[TestMethod, ExpectedException(typeof(InvalidOperationException))]
public void TestDeleteLine_Exception_AfterEnd() {
var rtb = new RichTextBox();
rtb.Text = "\n\n";
rtb.DeleteLine(3);
}
count += 0
... - Dave Cousineau