[Winodows Phone 7控制項詳解]Silverlight toolkit for Windows Phone 7.1控制項-5

11年11月初，微軟的silverlight toolkit for phone又放出四個新控制項，這四個控制項使用都要比之前的複雜，並且很有用。

6.AutoCompleteBox

這個控制項很像ajax裡的輸入框，可以聯想詞。不過需要自已產生一個詞庫檔案，還要編寫代碼來載入詞載。在silverlgiht toolkit sample裡面已經有這個範例程式碼了（loremIpsum.cs,loremIpsum.txt，這裡只是一個拉丁文的測試檔案，所以需要自已來實現字型檔檔案）。

        <Grid x:Name="ContentPanel" Grid.Row="1" Margin="12,0,12,0">
            <toolkit:AutoCompleteBox HorizontalAlignment="Left" Margin="63,43,0,0" Name="autoCompleteBox1" VerticalAlignment="Top" Width="317" Height="72" ItemsSource="{StaticResource words}" />
        </Grid>

xmlns:data="clr-namespace:testNewControls.Data"

    <phone:PhoneApplicationPage.Resources>
        <data:LoremIpsum x:Name="words"/>
    </phone:PhoneApplicationPage.Resources>

這個Resource定義一定要在AutoComepleteBox前面，不然會報一個很奇怪的錯誤。
LoremIpsum.cs的完整代碼如下：

// (c) Copyright Microsoft Corporation.
// This source is subject to the Microsoft Public License (Ms-PL).
// Please see http://go.microsoft.com/fwlink/?LinkID=131993 for details.
// All other rights reserved.

using System;
using System.Collections;
using System.Collections.Generic;
using System.IO;
using System.Text;
using System.Windows;
using System.Windows.Resources;

namespace testNewControls.Data
{

public static class Extension
    {
public static T Next<T>(this Random rnd, IList<T> list)
        {
return list[rnd.Next(list.Count)];
        }
    }

/// <summary>
/// A class to return paragraphs of random sentences or a word list from lorem ipsum data.
/// </summary>
    public class LoremIpsum : IEnumerable<string>
    {
public enum Capitalization
        {
            None,
            FirstWord,
            AllWords
        }

private static Random _rnd = new Random(42);

private static StringBuilder _builder = new StringBuilder();
private static List<string> _sentences;
private static List<string> _words;


/// <summary>
/// Returns random lorem ipsum sentences combined into a single string.
/// </summary>
/// <param name="sentenceCount">The nunmber of sentences.</param>
/// <returns>The paragraph, composed of random sentences.</returns>
        public static string GetParagraph(int sentenceCount)
        {
            EnsureSentences();

            _builder.Length = 0;

while (sentenceCount-- > 0)
            {
                _builder.Append(_rnd.Next(_sentences));
if (sentenceCount > 0)
                {
                    _builder.Append(' ');
                }
            }

return _builder.ToString();
        }

/// <summary>
/// Return an alphabetized, lower-case list of lorem ipsum words.
/// </summary>
        public static ICollection<string> Words
        {
get
            {
                EnsureWords();
return (ICollection<string>)_words;
            }
        }

/// <summary>
/// Get a string composed of random lorem ipsum words. Will not end with punctuation.
/// </summary>
/// <param name="wordCount">Number of words.</param>
/// <param name="capitalize">How to capitalize the words.</param>
/// <returns></returns>
        public static string GetWords(int wordCount, Capitalization capitalization)
        {
            EnsureWords();

            _builder.Length = 0;

while (wordCount-- > 0)
            {
int position = _builder.Length;
                _builder.Append(_rnd.Next(_words));
if (capitalization == Capitalization.AllWords || (position == 0 && capitalization == Capitalization.FirstWord))
                {
                    _builder[position] = char.ToUpper(_builder[position]);
                }

if (wordCount > 0)
                {
                    _builder.Append(' ');
                }
            }

return _builder.ToString();
        }

/// <summary>
/// Enumerates the Words property.
/// </summary>
/// <returns>The enumerator.</returns>
        public IEnumerator<string> GetEnumerator()
        {
return LoremIpsum.Words.GetEnumerator();
        }

/// <summary>
/// Enumerates the Words property.
/// </summary>
/// <returns>The enumerator.</returns>
        IEnumerator IEnumerable.GetEnumerator()
        {
return LoremIpsum.Words.GetEnumerator();
        }

/// <summary>
/// Reads the lorem ipsum sentences. Supplies some data in case reading fails, which
/// it will do at design time.
/// </summary>
        private static void EnsureSentences()
        {
if (_sentences == null)
            {
                _sentences = new List<string>();

                StreamResourceInfo info = Application.GetResourceStream(new Uri("Data/LoremIpsum.txt", UriKind.Relative));
if (info != null)
                {
                    Stream stream = info.Stream;
if (stream != null)
                    {
using (StreamReader reader = new StreamReader(stream))
                        {
while (!reader.EndOfStream)
                            {
                                _sentences.Add(reader.ReadLine());
                            }
                        };
                    }
                }

if (_sentences.Count == 0)
                {
                    _sentences.Add("Lorem ipsum dolor sit amet, consectetuer adipiscing elit.");
                    _sentences.Add("Maecenas porttitor congue massa.");
                    _sentences.Add("Fusce posuere, magna sed pulvinar ultricies, purus lectus malesuada libero, sit amet commodo magna eros quis urna.");
                    _sentences.Add("Nunc viverra imperdiet enim.");
                    _sentences.Add("Fusce est.");
                }
            }
        }

/// <summary>
/// Creates an alphabetized list of the words from the lorem ipsum text.
/// </summary>
        private static void EnsureWords()
        {
char[] separators = { ' ', ',', '.' };

            EnsureSentences();

if (_words == null)
            {
                Dictionary<string, object> temp = new Dictionary<string, object>();

foreach (string sentence in _sentences)
                {
string[] words = sentence.Split(separators, StringSplitOptions.RemoveEmptyEntries);
foreach (string word in words)
                    {
                        temp[word.ToLower()] = null;
                    }
                }

                _words = new List<string>(temp.Keys);
                _words.Sort();
            }
        }
    }
}