StringBuilder Constructor (String, Int32, Int32, Int32)


Initializes a new instance of the StringBuilder class from the specified substring and capacity.

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

public StringBuilder(
	string value,
	int startIndex,
	int length,
	int capacity


Type: System.String

The string that contains the substring used to initialize the value of this instance. If value is null, the new StringBuilder will contain the empty string (that is, it contains Empty).

Type: System.Int32

The position within value where the substring begins.

Type: System.Int32

The number of characters in the substring.

Type: System.Int32

The suggested starting size of the StringBuilder.

Exception Condition

capacity is less than zero.


startIndex plus length is not a position within value.

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 following example demonstrates how to call the StringBuilder constructor with the specified string.

string initialString = "Initial string for stringbuilder.";
int startIndex = 0;
int substringLength = 14;
int capacity = 255;
StringBuilder stringBuilder = new StringBuilder(initialString, 
    startIndex, substringLength, capacity);

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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