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//------------------------------------------------------------------------------
// <copyright file="LiteralText.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
//------------------------------------------------------------------------------
using System;
using System.ComponentModel;
using System.ComponentModel.Design;
using System.Drawing;
using System.Web;
using System.Web.UI;
using System.Web.UI.Design.WebControls;
using System.Web.UI.HtmlControls;
using System.Security.Permissions;
namespace System.Web.UI.MobileControls
{
/*
* Literal Text class. This is the control created for literal text in a form.
*
* Copyright (c) 2000 Microsoft Corporation
*/
/// <include file='doc\LiteralText.uex' path='docs/doc[@for="LiteralText"]/*' />
[
ControlBuilderAttribute(typeof(LiteralTextControlBuilder)),
ToolboxItem(false)
]
[AspNetHostingPermission(SecurityAction.LinkDemand, Level=AspNetHostingPermissionLevel.Minimal)]
[AspNetHostingPermission(SecurityAction.InheritanceDemand, Level=AspNetHostingPermissionLevel.Minimal)]
[Obsolete("The System.Web.Mobile.dll assembly has been deprecated and should no longer be used. For information about how to develop ASP.NET mobile applications, see http://go.microsoft.com/fwlink/?LinkId=157231.")]
public class LiteralText : PagedControl
{
// Note that this value doesn't relate to device specific info
// because this is simply a unit size to define how many characters
// to be counted as an item for pagination. Depending on each
// device's page weight, different numbers of items will be returned
// for display.
private static readonly int PagingUnitSize = ControlPager.DefaultWeight; // chars
/// <include file='doc\LiteralText.uex' path='docs/doc[@for="LiteralText.Text"]/*' />
[
Bindable(false),
Browsable(false),
]
public String Text
{
// Override MobileControl default behavior for InnerText
get
{
String s = (String)ViewState[MobileControl.InnerTextViewStateKey];
return s != null ? s : InnerText;
}
set
{
ViewState[MobileControl.InnerTextViewStateKey] = value;
}
}
// this attempts to split on word, return or sentence boundaries.
// use of '.' to indicate end of sentence assumes western languages
// perhaps if we get rid of '.' logic, '\n' preference will be sufficient
private int CalculateOffset(int itemIndex)
{
if (itemIndex == 0)
{
return 0;
}
int length = Text.Length;
int itemSize = (length / InternalItemCount) + 1;
int baseOffset = itemSize * itemIndex;
if (baseOffset >= length)
{
return length;
}
// this code scans to find an optimal break location.
String text = this.Text;
int scanLength = itemSize / 2;
int scanStop = baseOffset - scanLength;
int foundSpace = -1;
int foundReturn = -1;
int lastChar = -1;
for (int offset = baseOffset; offset > scanStop; offset--)
{
char c = text[offset];
if (c == '.' && Char.IsWhiteSpace((char)lastChar))
{
// this may exceed baseOffset by 1, but will never exceed totalChars
return offset + 1;
}
else if (foundReturn < 0 && c == '\n')
{
foundReturn = offset;
}
else if (foundSpace < 0 && Char.IsWhiteSpace(c)) // check performance of this
{
foundSpace = offset;
}
lastChar = c;
}
if (foundReturn > 0)
{
return foundReturn;
}
else if (foundSpace > 0)
{
return foundSpace;
}
return baseOffset;
}
/// <include file='doc\LiteralText.uex' path='docs/doc[@for="LiteralText.PagedText"]/*' />
public String PagedText
{
get
{
int index = FirstVisibleItemIndex;
int count = VisibleItemCount;
String text = Text;
if (count > text.Length)
{
return text;
}
int start = CalculateOffset(index);
int stop = CalculateOffset(index + count);
// If not at the beginning or end, skip spaces.
if (start > 0)
{
while (start < stop && Char.IsWhiteSpace(text[start]) )
{
start++;
}
}
if (stop < text.Length)
{
while (Char.IsWhiteSpace(text[stop - 1]) && stop > start)
{
stop--;
}
}
return (stop > start) ? text.Substring(start, stop - start) : String.Empty;
}
}
/// <include file='doc\LiteralText.uex' path='docs/doc[@for="LiteralText.InternalItemCount"]/*' />
protected override int InternalItemCount
{
get
{
return ((Text.Length / PagingUnitSize) + (((Text.Length % PagingUnitSize) > 0) ? 1 : 0));
}
}
/// <include file='doc\LiteralText.uex' path='docs/doc[@for="LiteralText.ItemWeight"]/*' />
protected override int ItemWeight
{
get
{
return PagingUnitSize;
}
}
internal override bool TrimInnerText
{
get
{
return false;
}
}
}
/*
* Control builder for literal text.
*
* Copyright (c) 2000 Microsoft Corporation
*/
/// <include file='doc\LiteralText.uex' path='docs/doc[@for="LiteralTextControlBuilder"]/*' />
[AspNetHostingPermission(SecurityAction.LinkDemand, Level=AspNetHostingPermissionLevel.Minimal)]
[AspNetHostingPermission(SecurityAction.InheritanceDemand, Level=AspNetHostingPermissionLevel.Minimal)]
[Obsolete("The System.Web.Mobile.dll assembly has been deprecated and should no longer be used. For information about how to develop ASP.NET mobile applications, see http://go.microsoft.com/fwlink/?LinkId=157231.")]
public class LiteralTextControlBuilder : MobileControlBuilder
{
/// <include file='doc\LiteralText.uex' path='docs/doc[@for="LiteralTextControlBuilder.AllowWhitespaceLiterals"]/*' />
public override bool AllowWhitespaceLiterals()
{
return true;
}
}
}
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