CODEWITHSUNDEEP
asp.netvb.netstringtext
Vincent
Vincent

Reputation: 27

remove double linebreaks in string

I am developing a asp.net web application, i have a string (with a value in it from a database), with multiple lines that i put in a TextBox with mulitline type. (textarea)

Now the problem is, that in the string are multiple lines, with much empty space. so i want the remove only the double linebreaks.

example of my textbox:

+++++++++++++++++++++++++++++++++++++++++++++++++++++
{empty}
{empty}
'This is some text in the textbox on line 3
'some text on line 4
{empty}
'some text on line 6
{empty}
{empty}
'some text on line 9
{empty}
+++++++++++++++++++++++++++++++++++++++++++++++++++++
now somehow i want to remove line 1 and 2, and line 7 and 8

thanks in advance

Upvotes: 3

Views: 2577

Answers (4)

Predator
Predator

Reputation: 1275

Here is the solution:

'now rebuild your example string
Dim Empty As String = Chr(13) & Chr(10)

Dim Sb As New System.Text.StringBuilder
Sb.Append("+++++++++++++++++++++++++++++++++++++++++++++++++++++")
Sb.Append(Empty)
Sb.Append(Empty)
Sb.Append(Empty & "This is some text in the textbox on line 3")

Sb.Append(Empty & "some text on line 4")
Sb.Append(Empty)
Sb.Append(Empty & "some text on line 6")
Sb.Append(Empty)
Sb.Append(Empty)
Sb.Append(Empty & "some text on line 9")
Sb.Append(Empty)
Sb.Append(Empty)
Sb.Append("+++++++++++++++++++++++++++++++++++++++++++++++++++++")
Dim YourString As String = Sb.ToString
MessageBox.Show(YourString)

'now replace the double empty
Dim result As String
result = YourString.Replace(Empty & Empty & Empty, Empty)
MessageBox.Show(result)

NOTE: This solution has been tested OK with Visual Studio 2010.

Upvotes: 1

tiago2014
tiago2014

Reputation: 3461

The following code removes double empty lines at the beginning, and also double empty lines anywhere in the textbox.

Dim myText as String = TextBox1.Text
myText = Regex.Replace(myText, "^(\r\n\r\n)(.*)", "$2")
myText = Regex.Replace(myTextt, "(.*\r\n)(\r\n\r\n)(.*)", "$1$3")
TextBox1.Text = myText

In the example given, it would remove lines 1 and 2, and lines 7 and 8.

Upvotes: 0

Chris Haas
Chris Haas

Reputation: 55417

The way I usually do this is to convert all of the various line breaks into a single one that I can manage, de-dupe and convert back to vbNewLine:

    '//Convert all line break types to vbCr/ASCII 13
    T = T.Replace(vbNewLine, vbCr).Replace(vbLf, vbCr)
    '//Loop until all duplicate returns are removed
    Do While T.Contains(vbCr & vbCr)
        T = T.Replace(vbCr & vbCr, vbCr)
    Loop
    '//Check to see if the string has one at the start to remove
    If T.StartsWith(vbCr) Then T = T.TrimStart(Chr(13))

    '//Convert back to standard windows line breaks
    T = T.Replace(vbCr, vbNewLine)

Upvotes: 0

dbasnett
dbasnett

Reputation: 11773

This will get rid of all empty lines.

    Dim splt() As Char = New Char() {ControlChars.Lf, ControlChars.Cr}
    Dim lines() As String = TextBox1.Text.Split(splt, StringSplitOptions.RemoveEmptyEntries)
    TextBox1.Lines = lines

This looks like it will get rid of multiple newlines

    Dim s As String = TextBox1.Text.Replace(Environment.NewLine, ControlChars.Cr)
    Dim lines As New List(Of String)
    lines.AddRange(s.Split(New Char() {ControlChars.Cr}))

    For x As Integer = lines.Count - 1 To 1 Step -1
        If lines(x) = "" AndAlso lines(x - 1) = "" Then
            lines.RemoveAt(x)
        End If
    Next
    TextBox1.Lines = lines.ToArray

Upvotes: 0

Related Questions