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StringBuilder.Append Method (String)


Appends a copy of the specified string to this instance.

Namespace:   System.Text
Assembly:  mscorlib (in mscorlib.dll)

public StringBuilder Append(
	string value


Type: System.String

The string to append.

Return Value

Type: System.Text.StringBuilder

A reference to this instance after the append operation has completed.

Exception Condition

Enlarging the value of this instance would exceed MaxCapacity.

The Append(String) method modifies the existing instance of this class; it does not return a new class instance. Because of this, you can call a method or property on the existing reference and you do not have to assign the return value to a StringBuilder object, as the following example illustrates.

bool flag = false;
System.Text.StringBuilder sb = new System.Text.StringBuilder();
sb.Append("The value of the flag is ").Append(flag).Append(".");
// The example displays the following output:
//       The value of the flag is False.

If value is null, no changes are made.

The capacity of this instance is adjusted as needed.

Notes to Callers:

In the.NET Framework 4 and the .NET Framework 4.5, when you instantiate the StringBuilder object by calling the StringBuilder(Int32, Int32) constructor, both the length and the capacity of the StringBuilder instance can grow beyond the value of its MaxCapacity property. This can occur particularly when you call the Append and AppendFormat methods to append small strings.

Universal Windows Platform
Available since 4.5
.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
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