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StringBuilder Constructor (Int32, Int32)

Initializes a new instance of the StringBuilder class that starts with a specified capacity and can grow to a specified maximum.

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

Public Sub New ( _
	capacity As Integer, _
	maxCapacity As Integer _


Type: System.Int32
The suggested starting size of the StringBuilder.
Type: System.Int32
The maximum number of characters the current string can contain.


maxCapacity is less than one, capacity is less than zero, or capacity is greater than maxCapacity.

The capacity parameter defines the maximum number of characters that can be stored in the memory allocated by the current instance. Its value is assigned to the Capacity property. If the number of characters to be stored in the current instance exceeds this capacity value, the StringBuilder object allocates additional memory to store them.

If capacity is zero, the implementation-specific default capacity is used.

The maxCapacity property defines the maximum number of characters that the current instance can hold. Its value is assigned to the MaxCapacity property. If the number of characters to be stored in the current instance exceeds this maxCapacity value, the StringBuilder object does not allocate additional memory, but instead throws an exception.

Notes to Callers

In the .NET Framework 4, when you instantiate the StringBuilder object by calling the StringBuilder 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.

The following example demonstrates how to call the StringBuilder constructor with a specified capacity and maximum capacity.

Dim capacity As Integer = 255
Dim maxCapacity As Integer = 1024
Dim stringBuilder As New StringBuilder(capacity, maxCapacity)

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Portable Class Library

Supported in: Portable Class Library

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.