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StringBuilder.EnsureCapacity Method

Ensures that the capacity of this instance of StringBuilder is at least the specified value.

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

public int EnsureCapacity (
	int capacity
)
public int EnsureCapacity (
	int capacity
)
public function EnsureCapacity (
	capacity : int
) : int

Parameters

capacity

The minimum capacity to ensure.

Return Value

The new capacity of this instance.

Exception typeCondition

ArgumentOutOfRangeException

capacity is less than zero.

-or-

Enlarging the value of this instance would exceed MaxCapacity.

If the current capacity is less than the capacity parameter, memory for this instance is reallocated to hold at least capacity number of characters; otherwise, no memory is changed.

The following code example demonstrates the EnsureCapacity method.

using System;
using System.Text;

class Sample 
{
    public static void Main() 
    {
    StringBuilder sb1 = new StringBuilder("abc");
    StringBuilder sb2 = new StringBuilder("abc", 16);

    Console.WriteLine();
    Console.WriteLine("a1) sb1.Length = {0}, sb1.Capacity = {1}", sb1.Length, sb1.Capacity);
    Console.WriteLine("a2) sb2.Length = {0}, sb2.Capacity = {1}", sb2.Length, sb2.Capacity);
    Console.WriteLine("a3) sb1.ToString() = \"{0}\", sb2.ToString() = \"{1}\"", 
                           sb1.ToString(),       sb2.ToString());
    Console.WriteLine("a4) sb1 equals sb2: {0}", sb1.Equals(sb2));

    Console.WriteLine();
    Console.WriteLine("Ensure sb1 has a capacity of at least 50 characters.");
    sb1.EnsureCapacity(50);

    Console.WriteLine();
    Console.WriteLine("b1) sb1.Length = {0}, sb1.Capacity = {1}", sb1.Length, sb1.Capacity);
    Console.WriteLine("b2) sb2.Length = {0}, sb2.Capacity = {1}", sb2.Length, sb2.Capacity);
    Console.WriteLine("b3) sb1.ToString() = \"{0}\", sb2.ToString() = \"{1}\"", 
                           sb1.ToString(),       sb2.ToString());
    Console.WriteLine("b4) sb1 equals sb2: {0}", sb1.Equals(sb2));

    Console.WriteLine();
    Console.WriteLine("Set the length of sb1 to zero.");
    Console.WriteLine("Set the capacity of sb2 to 51 characters.");
    sb1.Length = 0;
    sb2.Capacity = 51;

    Console.WriteLine();
    Console.WriteLine("c1) sb1.Length = {0}, sb1.Capacity = {1}", sb1.Length, sb1.Capacity);
    Console.WriteLine("c2) sb2.Length = {0}, sb2.Capacity = {1}", sb2.Length, sb2.Capacity);
    Console.WriteLine("c3) sb1.ToString() = \"{0}\", sb2.ToString() = \"{1}\"", 
                           sb1.ToString(),       sb2.ToString());
    Console.WriteLine("c4) sb1 equals sb2: {0}", sb1.Equals(sb2));
    }
}
/*
This example produces the following results:

a1) sb1.Length = 3, sb1.Capacity = 16
a2) sb2.Length = 3, sb2.Capacity = 16
a3) sb1.ToString() = "abc", sb2.ToString() = "abc"
a4) sb1 equals sb2: True

Ensure sb1 has a capacity of at least 50 characters.

b1) sb1.Length = 3, sb1.Capacity = 51
b2) sb2.Length = 3, sb2.Capacity = 16
b3) sb1.ToString() = "abc", sb2.ToString() = "abc"
b4) sb1 equals sb2: False

Set the length of sb1 to zero.
Set the capacity of sb2 to 51 characters.

c1) sb1.Length = 0, sb1.Capacity = 51
c2) sb2.Length = 3, sb2.Capacity = 51
c3) sb1.ToString() = "", sb2.ToString() = "abc"
c4) sb1 equals sb2: False
*/

// This example demonstrates StringBuilder.EnsureCapacity
//                           StringBuilder.Capacity
//                           StringBuilder.Length
//                           StringBuilder.Equals
import System.*;
import System.Text.*;

class Sample
{
    public static void main(String[] args)
    {
        StringBuilder sb1 = new StringBuilder("abc");
        StringBuilder sb2 = new StringBuilder("abc", 16);

        Console.WriteLine();
        Console.WriteLine("a1) sb1.get_Length() = {0}, " 
            + "sb1.get_Capacity() = {1}", 
            System.Convert.ToString(sb1.get_Length()), 
            System.Convert.ToString(sb1.get_Capacity()));
        Console.WriteLine("a2) sb2.get_Length() = {0}, " 
            + "sb2.get_Capacity() = {1}", 
            System.Convert.ToString(sb2.get_Length()), 
            System.Convert.ToString(sb2.get_Capacity()));
        Console.WriteLine("a3) sb1.ToString() = \"{0}\", " 
            + "sb2.ToString() = \"{1}\"", sb1.ToString(), sb2.ToString());
        Console.WriteLine("a4) sb1 equals sb2: {0}", 
            System.Convert.ToString(sb1.Equals(sb2)));

        Console.WriteLine();
        Console.WriteLine("Ensure sb1 has a capacity of at least 50 " 
            + "characters.");
        sb1.EnsureCapacity(50);

        Console.WriteLine();
        Console.WriteLine("b1) sb1.get_Length() = {0}, " 
            + "sb1.get_Capacity() = {1}", 
            System.Convert.ToString(sb1.get_Length()), 
            System.Convert.ToString(sb1.get_Capacity()));
        Console.WriteLine("b2) sb2.get_Length() = {0}, " 
            + "sb2.get_Capacity() = {1}", 
            System.Convert.ToString(sb2.get_Length()), 
            System.Convert.ToString(sb2.get_Capacity()));
        Console.WriteLine("b3) sb1.ToString() = \"{0}\", " 
            + "sb2.ToString() = \"{1}\"", sb1.ToString(), sb2.ToString());
        Console.WriteLine("b4) sb1 equals sb2: {0}", 
            System.Convert.ToString(sb1.Equals(sb2)));

        Console.WriteLine();
        Console.WriteLine("Set the length of sb1 to zero.");
        Console.WriteLine("Set the capacity of sb2 to 51 characters.");
        sb1.set_Length(0);
        sb2.set_Capacity(51);

        Console.WriteLine();
        Console.WriteLine("c1) sb1.get_Length() = {0}, "
            + "sb1.get_Capacity() = {1}", 
            System.Convert.ToString(sb1.get_Length()), 
            System.Convert.ToString(sb1.get_Capacity()));
        Console.WriteLine("c2) sb2.get_Length() = {0}, " 
            + "sb2.get_Capacity() = {1}", 
            System.Convert.ToString(sb2.get_Length()), 
            System.Convert.ToString(sb2.get_Capacity()));
        Console.WriteLine("c3) sb1.ToString() = \"{0}\", " 
            + "sb2.ToString() = \"{1}\"", sb1.ToString(), sb2.ToString());
        Console.WriteLine("c4) sb1 equals sb2: {0}", 
            System.Convert.ToString(sb1.Equals(sb2)));
    } //main
} //Sample
/*
This example produces the following results:

a1) sb1.get_Length() = 3, sb1.get_Capacity() = 16
a2) sb2.get_Length() = 3, sb2.get_Capacity() = 16
a3) sb1.ToString() = "abc", sb2.ToString() = "abc"
a4) sb1 equals sb2: True

Ensure sb1 has a capacity of at least 50 characters.

b1) sb1.get_Length() = 3, sb1.get_Capacity() = 50
b2) sb2.get_Length() = 3, sb2.get_Capacity() = 16
b3) sb1.ToString() = "abc", sb2.ToString() = "abc"
b4) sb1 equals sb2: False

Set the length of sb1 to zero.
Set the capacity of sb2 to 51 characters.

c1) sb1.get_Length() = 0, sb1.get_Capacity() = 50
c2) sb2.get_Length() = 3, sb2.get_Capacity() = 51
c3) sb1.ToString() = "", sb2.ToString() = "abc"
c4) sb1 equals sb2: False
*/

Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

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

.NET Framework

Supported in: 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 2.0

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