Append, AppendLine. To add string data to a StringBuilder in VB.NET programs, we call the Append or AppendLine functions. These functions can be used in a single statement, or chained together.
With Append, no extra characters are added after the argument. But AppendLine adds a newline sequence, which is platform-dependent, and makes using StringBuilder more convenient.
Append example. Usually when using StringBuilder, we call Append in a loop—here we have 2 For-loops. We call Append 3 times in each loop.
Version 1 We call Append 3 times in the body of the For-loop, and each call to Append occurs on its own line.
Version 2 We chain calls to Append, so that we have only one line of code in the For-loop here. The result is the same as the previous loop.
Imports System.Text
Module Module1
Sub Main()
Const s As String = "(s)"' Version 1: call Append in loop.
Dim builder = New StringBuilder()
For i = 0 To 2
builder.Append("Start")
builder.Append(s)
builder.Append("End")
Next
' Version 2: call Append in loop in same statement.
Dim builder2 = New StringBuilder()
For i = 0 To 2
builder2.Append("Start").Append( s).Append("End")
Next
Console.WriteLine("BUILDER: {0}", builder)
Console.WriteLine("BUILDER 2: {0}", builder2)
End Sub
End ModuleBUILDER: Start(s)EndStart(s)EndStart(s)End
BUILDER 2: Start(s)EndStart(s)EndStart(s)End
AppendLine example. When we call AppendLine, a newline sequence is added automatically at the end of every call. This is equal to the current platform's NewLine property.
Info When no arguments are passed to AppendLine, only a newline sequence is appended.
Imports System.Text
Module Module1
Sub Main()
' Use AppendLine.
Dim builder = New StringBuilder()
builder.AppendLine("One")
builder.AppendLine()
builder.AppendLine("Two").AppendLine("Three")
Console.Write(builder)
End Sub
End ModuleOne
Two
Three
Along with ToString, the Append and AppendLine functions are the most commonly-used ones on StringBuilder. AppendLine has the extra convenience of a newline sequence on each call.
Dot Net Perls is a collection of tested code examples. Pages are continually updated to stay current, with code correctness a top priority.
Sam Allen is passionate about computer languages. In the past, his work has been recommended by Apple and Microsoft and he has studied computers at a selective university in the United States.
