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发布时间:2015-09-26 作者:网络 阅读:193次
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概述

建立自己的地址栏

建立示例程序

最后

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概述:
本文描述了如何建立一个简单的、常用的用户控件——地址栏。

相信只要上网的朋友,都知道IE里面有一个提供大家输入你想去的网站的输入框。在该输入框中,你只需要输入部分字符,它在其下拉列表框中,就显示出来与你所输入相关的内容(记忆功能)。

如果只要求输入字符串就可以的话。那么,我们可以直接使用TextBox等控件完成输入框。但如果你要让你的输入框有记忆功能的话。那么,我们所需要的就是要求能把以前所输入的内容读取出来。

好了,废话说了半天了。那么,我们从下面开始讲解如何让我们的地址栏有记忆功能的。

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建立自己的地址栏:
首先,我们要分两步走。

第一步,我们首先要明白,我们IE地址栏的历史记忆内容是从哪来的。因为只有知道它是从哪来的,我们才能明白我们的数据嘛。

那么,我们先看一下,IE在regedit(注册表)里面都有些什么内容。因为regeidt是Windows里面一个非常不错的数据库(^_^),它可以把整台机子相关的一些东西都存放在里面。

在regedit里面,与IE相关的内容有这些:




当然,这只是一部分,还有一部分是:



我们要的是第一幅图片里面的“Software\Microsoft\Internet Explorer\TypedURLs”的数据。不然,我们写的记忆功能就起不了什么作用了。或者,出现一些其它数据。要知道,在regedit里面保存的数据可都是一些关键数据。如果一不小心被人XX掉的话,那么,L。

OK,现在已经找到我们要的数据是从什么地方来的了。那么,我们就要开始打造我们自己的带记忆功能的地址栏了。

当然,打到这些够了吗?当然,够是够了。但,你不想让你的地址栏功能再强大一点吗?那么,我们写这样的一个类来看看:

1、 新建项目,选择新建类库,名字就顺意了。比如:ControlSet.URLControl。

2、 在资源管理里面添加引用System.Windows.Forms.dll。

3、 然后,在资源管理器里面把Class1.cs改为UnManagedMethods.cs,然后,用下面的代码替换:

using System;

using System.Runtime.InteropServices;



namespace ControlSet.URLControl

{

[StructLayout(LayoutKind.Sequential)]

internal struct Rect

{

public int left;

public int top;

public int right;

public int bottom;

}



[StructLayout(LayoutKind.Sequential)]

internal struct ComboBoxInfo

{

public int cbSize;

public Rect rcItem;

public Rect rcButton;

public IntPtr stateButton;

public IntPtr hwndCombo;

public IntPtr hwndEdit;

public IntPtr hwndList;

}



///

/// All unmanaged DllImport methods used in this assembly

///


internal class UnManagedMethods

{

[DllImport("User32.dll")]

internal static extern bool GetComboBoxInfo(IntPtr hwndCombo, ref ComboBoxInfo info);



[DllImport("Shlwapi.dll")]

internal static extern void SHAutoComplete(IntPtr hwnd, IntPtr flags);

}

}




第二步,我们的地址栏出现了。那么,要用什么做为它的基控件呢?

因为我们要有记忆功能,那么,当然,要有一个能下拉的东西了。什么?ComboBox就是最好的选择。那好,我们开始用ComboBox来构建我们自己的控件。

namespace ControlSet.URLControl

{

///

/// A control that extends the regular combo box to show URLs.

///


public class URLComboBox : ComboBox

{

///

/// Initilaizes a new instance of URLComboBox

///


public URLComboBox() : base()

{

}

}

}




首先,我们添加如下引用:

using Microsoft.Win32;




在该控件内要用到下面一些东西,我们给它添加如下代码(添加到命名空间里面):

///

/// A simple enumeration that wraps various auto complete flags of SHAutoComplete.

/// See documenation of SHAutoComplete for details

///


[Flags]

public enum AutoCompleteFlags : int

{

///

/// This includes the File System as well as the rest of the shell (Desktop\My Computer\Control Panel\)

///


FileSystem = 0x00000001,

///

/// URLs in the User's History

///


URLHistory = 0x00000002,

///

/// URLs in the User's Recently Used list.

///


URLMRU = 0x00000004,

///

/// Use the tab to move thru the autocomplete possibilities instead of to the next dialog/window control.

///


UseTab = 0x00000008,

///

/// This includes the File System

///


FileSystemOnly = 0x00000010,

///

/// Same as FileSystemOnly except it only includes directories, UNC servers, and UNC server shares.

///


FileSystemDirs = 0x00000020,

///

/// Ignore the registry default and force the auto suggest feature on.

///


AutoSuggestForceOn = 0x10000000,

///

/// Ignore the registry default and force the auto suggest feature off

///


AutoSuggestForceOff = 0x20000000,

///

/// Ignore the registry default and force the auto append on.

///


AutoAppendForceOn = 0x40000000,

///

/// Ignore the registry default and force auto append off.

///


AutoAppendForceOff = -2147483648

}



///

/// Enumeration for possible types of registry base keys for storing most recntly typed URLs

///


public enum MRUKeyHive : int

{

///

/// Value that indicates HKEY_CURRENT_USER should be used for MRUKey property

///


CurrentUser = 1,

///

/// Value that indicates HKEY_LOCAL_MACHINE should be used for MRUKey property

///


LocalMachine = 2,

}


然后,再在该类里面加载如下代码来完成它应该有的功能:

///

/// A control that extends the regular combo box to show URLs.

///


public class URLComboBox : ComboBox

{

///

/// Member variable which stores the autocomplete flags

///


private AutoCompleteFlags _flags = AutoCompleteFlags.FileSystem | AutoCompleteFlags.URLHistory | AutoCompleteFlags.URLMRU;

///

/// Member variable which stores the mru key

///


private string _mruKey = @"Software\Microsoft\Internet Explorer\TypedURLs";

///

/// Member variable which stores the mru key hive

///


private MRUKeyHive _mruKeyHive = MRUKeyHive.CurrentUser;



///

/// Initilaizes a new instance of URLComboBox

///


public URLComboBox() : base()

{

}



///

/// Gets the registry key where MRU URLs are stored

///


/// Indicates whether to get the key so that it values written to it

/// RegistryKey object for the MRU registry key or null if none exists

private RegistryKey GetMRUKey(bool writable)

{

if (_mruKey.Length == 0)

return null;



RegistryKey ret = null;



switch(_mruKeyHive)

{

case MRUKeyHive.LocalMachine:

ret = Registry.LocalMachine.OpenSubKey(_mruKey, writable);

break;

case MRUKeyHive.CurrentUser:

ret = Registry.CurrentUser.OpenSubKey(_mruKey, writable);

break;

}



return ret;

}



///

/// Writes information about any ignored exception to the trace.

///


/// The exception which is being ignored

private void TraceIgnoredError(Exception e)

{

//It's ok if there is any error

System.Diagnostics.Trace.WriteLine(e.Message);

System.Diagnostics.Trace.WriteLine(e.StackTrace);

}



///

/// Utility function to fill the combob box most recently typed URLs read from registry.

///


private void MRUFill()

{

if (DesignMode)

return;



RegistryKey mruKey = null;



try

{

int i = 1;



string strFormat = "url{0}";

object defaultValue = String.Empty;

object url;



mruKey = GetMRUKey(false);



if (mruKey != null)

{

while((url = mruKey.GetValue(String.Format(strFormat, i), defaultValue)) != defaultValue)

{

Items.Add(url);

i++;

}

}

}

catch(Exception e)

{

TraceIgnoredError(e);

}

finally

{

if (mruKey != null)

mruKey.Close();

}

}



///

/// Gets or sets the auto complete flags

///


[Description("Gets or sets the auto complete flags")]

public AutoCompleteFlags Flags

{

get

{

return _flags;

}

set

{

_flags = value;

}

}



///

/// Gets or sets the registry key name where the combo box maintains MRU list.

///


[DescriptionAttribute("The registry key name where the combo box maintains MRU list")]

public string MRUKey

{

get

{

return _mruKey;

}

set

{

_mruKey = value;

}

}



///

/// Gets or sets the registry key hive for the MRUKey property.

///


[DescriptionAttribute("The registry hive where the combo box maintains MRU list")]

public MRUKeyHive MRUKeyHive

{

get

{

return _mruKeyHive;

}

set

{

_mruKeyHive = value;

}

}



///

/// Writes the recntly typed URL to the registry if it is not already there

///


///

protected override void OnValidated(System.EventArgs e)

{

if (DesignMode)

return;



if ((Text.Length != 0) && (Items.IndexOf(Text) == -1))

{

Items.Add(Text);



RegistryKey mruKey = null;



//Finally add it to the registry

try

{

mruKey = GetMRUKey(true);



if (mruKey != null)

mruKey.SetValue(String.Format("url{0}", Items.Count), Text);

}

catch(Exception ex)

{

TraceIgnoredError(ex);

}

finally

{

if (mruKey != null)

mruKey.Close();

}

}



base.OnValidated(e);

}



///

/// Finds the handle to the edit control and calls SHAutoComplete on it.

/// Also fills the combobox from the values read from the registry

///


/// Ignored

protected override void OnHandleCreated(System.EventArgs e)

{

base.OnHandleCreated(e);



if (DesignMode)

return;



//This is the right place do auto completion

ComboBoxInfo info = new ComboBoxInfo();

info.cbSize = System.Runtime.InteropServices.Marshal.SizeOf(info);



if (UnManagedMethods.GetComboBoxInfo(Handle, ref info))

{

UnManagedMethods.SHAutoComplete(info.hwndEdit, (IntPtr)_flags);

}



MRUFill();

}

}


好了,那么,到现在为止。我们的带记忆功能的地址栏已经构建完成。

你可以在菜单【生成(B)】里面,调试生成解决方案。

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建立示例程序:
1、 新建项目,选择Windows应用程序,名称:TestrulComboBox。

2、 我们把我们所需要的控件放到工具箱里面。在工具箱上面点右键。添加/移除项。打开Com组件。如下图:



3、 再把我们自己写的控件也放到工具箱里面。如上图,点击里面的浏览按钮。找到你上一个解决方案存放的目录,然后,找出它所生成的动态链接库文件。就可以直接添加到工具箱上面了。

4、 在现有的项目内,把拖放刚才添加到工具箱上面的Microsoft Web 浏览器控件,和刚才刚才写好的控件,拖放到主窗口上面。并进行排列。

5、 添加一个控钮。

6、 双击按钮,生成事件,并在事件中输入如下代码:

Cursor currentCursor = Cursor.Current;

try

{

Cursor.Current = Cursors.WaitCursor;



object arg1 = 0; object arg2 = ""; object arg3 = ""; object arg4 = "";

axWebBrowser1.Navigate(urlComboBox1.Text,ref arg1,ref arg2, ref arg3, ref arg4);

}

finally

{

Cursor.Current = currentCursor;

}




7、 生成解决方案。

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最后:
好了,你也可以自己试着做一个自己的、个性化的浏览器了。如果还想再加其他功能的话。那就不属于这一篇文章的目的了。J



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