更新：2007 年 11 月
提供一种用于串联字符串的机制。
命名空间：Sys
**继承：**无
var stringBuilderVar = StringBuilder(string);
构造函数
- Sys.StringBuilder 构造函数
创建 StringBuilder 的新实例，并（可选）接受要串联的初始文本。
成员
Sys.StringBuilder append 方法
将一个字符串追加到 StringBuilder 实例的末尾。Sys.StringBuilder appendLine 方法
将一个带行终止符的新字符串追加到 StringBuilder 实例的末尾。Sys.StringBuilder clear 方法
清除 StringBuilder 实例的内容。Sys.StringBuilder isEmpty 方法
确定 StringBuilder 实例是否有任何内容。Sys.StringBuilder toString 方法
从 StringBuilder 实例的内容创建一个字符串。
备注
StringBuilder 类表示一个可变字符串，提供了一种将字符串序列串联起来的机制。
示例
下面的示例演示如何创建新的 StringBuilder 实例，如何调用 append 方法来添加一行文本。之后，代码调用 appendLine 方法将一个带行终止符的字符串追加到字符串末尾。最后，代码调用 toString 方法，并传递一个“|”字符作为分隔符，插在 StringBuilder 所返回的字符串的各个元素之间。
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
<title>Samples</title>
</head>
<body>
<form id="form1" runat="server">
<asp:ScriptManager runat="server" ID="ScriptManager1">
</asp:ScriptManager>
<script type="text/javascript">
function buildAString(title){
var headTagStart = "<head>";
var headTagEnd = "</head>";
var titleTagStart = "<title>";
var titleTagEnd = "</title>";
var sb = new Sys.StringBuilder(this._headTagStart);
sb.append(titleTagEnd);
sb.append(title);
sb.append(titleTagEnd);
sb.append(headTagEnd);
// Displays: "The result: <head><title>A Title</title></head>"
alert("The result" + sb.toString());
}
var title = "A Title";
buildAString(title);
</script>
</form>
</body>
</html>
Imports System.Text
Public Module App
Public Sub Main()
' Create a StringBuilder that expects to hold 50 characters.
' Initialize the StringBuilder with "ABC".
Dim sb As New StringBuilder("ABC", 50)
' Append three characters (D, E, and F) to the end of the StringBuilder.
sb.Append(New Char() {"D"c, "E"c, "F"c})
' Append a format string to the end of the StringBuilder.
sb.AppendFormat("GHI{0}{1}", "J"c, "k"c)
' Display the number of characters in the StringBuilder and its string.
Console.WriteLine("{0} chars: {1}", sb.Length, sb.ToString())
' Insert a string at the beginning of the StringBuilder.
sb.Insert(0, "Alphabet: ")
' Replace all lowercase k's with uppercase K's.
sb.Replace("k", "K")
' Display the number of characters in the StringBuilder and its string.
Console.WriteLine("{0} chars: {1}", sb.Length, sb.ToString())
End Sub
End Module
' This code produces the following output.
'
' 11 chars: ABCDEFGHIJk
' 21 chars: Alphabet: ABCDEFGHIJK
using System;
using System.Text;
public sealed class App
{
static void Main()
{
// Create a StringBuilder that expects to hold 50 characters.
// Initialize the StringBuilder with "ABC".
StringBuilder sb = new StringBuilder("ABC", 50);
// Append three characters (D, E, and F) to the end of the StringBuilder.
sb.Append(new char[] { 'D', 'E', 'F' });
// Append a format string to the end of the StringBuilder.
sb.AppendFormat("GHI{0}{1}", 'J', 'k');
// Display the number of characters in the StringBuilder and its string.
Console.WriteLine("{0} chars: {1}", sb.Length, sb.ToString());
// Insert a string at the beginning of the StringBuilder.
sb.Insert(0, "Alphabet: ");
// Replace all lowercase k's with uppercase K's.
sb.Replace('k', 'K');
// Display the number of characters in the StringBuilder and its string.
Console.WriteLine("{0} chars: {1}", sb.Length, sb.ToString());
}
}
// This code produces the following output.
//
// 11 chars: ABCDEFGHIJk
// 21 chars: Alphabet: ABCDEFGHIJK
using namespace System;
using namespace System::Text;
int main()
{
// Create a StringBuilder that expects to hold 50 characters.
// Initialize the StringBuilder with "ABC".
StringBuilder^ sb = gcnew StringBuilder("ABC", 50);
// Append three characters (D, E, and F) to the end of the
// StringBuilder.
sb->Append(gcnew array<Char>{'D', 'E', 'F'});
// Append a format string to the end of the StringBuilder.
sb->AppendFormat("GHI{0}{1}", (Char)'J', (Char)'k');
// Display the number of characters in the StringBuilder
// and its string.
Console::WriteLine("{0} chars: {1}", sb->Length, sb->ToString());
// Insert a string at the beginning of the StringBuilder.
sb->Insert(0, "Alphabet: ");
// Replace all lowercase k's with uppercase K's.
sb->Replace('k', 'K');
// Display the number of characters in the StringBuilder
// and its string.
Console::WriteLine("{0} chars: {1}", sb->Length, sb->ToString());
}
// This code produces the following output.
//
// 11 chars: ABCDEFGHIJk
// 21 chars: Alphabet: ABCDEFGHIJK