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Haven't seen a book yet that lists recursion as a loop construct; normally they only mention things such as for, while and do.
One must be careful, if the code is written in such a way that tail recursion is possible, then sooner or later (probably later) MS may come with a C# compiler that turns the recursive code into a loop, which to the OP (or his teacher?) would be unacceptable.
Going one step further, our computers execute loops all the time: fetch instruction, decode instruction, execute instruction; whether coded in micro-code or implemented in parallel hardware, each little piece is doing its job over and over. So maybe it can't be done? Or maybe yours is the solution they wanted...
Luc Pattyn [Forum Guidelines] [My Articles]
The quality and detail of your question reflects on the effectiveness of the help you are likely to get.
Show formatted code inside PRE tags, and give clear symptoms when describing a problem.
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Luc Pattyn wrote: you'll need stronger lambda magic,
You're still using a loop then, you're just applying a layer of obfuscation to hide it. 
The European Way of War: Blow your own continent up.
The American Way of War: Go over and help them.
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this is a bad question ya know?
what is supposed to go in the dictionary?
I can only make some guess....
first you can't avoid a loop, so here woud be one
Rand r = new Random();<br />
foreach(var s in lst) dic[rand.Netx()] = s;
but maybe we could use some LINQ magic to hide the loop?
Random r = new Random();<br />
Dictionary<int , string> dic = new Dictionary<int , string>();<br />
dic = lst.ToDictionary <string, int>(s => r.Next());
How about that?! 
A train station is where the train stops. A bus station is where the bus stops. On my desk, I have a work station....
_________________________________________________________
My programs never have bugs, they just develop random features.
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StreamReader bfr = File.OpenText(@"D:\Documents and Settings\home\Desktop\normal.txt");
Dictionary < string , int > dic = new Dictionary < string , int > ();
string[] str = bfr.ReadToEnd().Replace("\r","").Replace("\n"," ").Replace(" "," ").Split(' ');
int var = 1;
foreach (string i in str)
{
if(dic.TryGetValue(i,out var))
dic[i]++;
else
dic.Add(i,1);
}
foreach(KeyValuePair < string , int > i in dic)
if(i.Value > 1)
Console.WriteLine(i.Key + " " + i.Value);
Console.ReadLine();
THIS WAS THE TASK BUT I HAVE DONE IT USING LOOP.
I WANT IT TO BE DONE without USING LOOP
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If I understand your question correctly, you want a List<string> which looks like this:
Value1
Value2
Value3
Value4
Value1
to be converted to a Dictionary<string, int> which looks like this:
{Value1, 2}
{Value2, 1}
{Value3, 1}
{Value4, 1}
The problem is that the first argument of ToDictionary should provide a method to get the key from the value. You want to get the value from the key, so ToDictionary probably won't help you here. You could probably create a LINQ expression which provides a collection of KeyValuePair<string, int>, but IMHO it may not be worth it. It may be quicker to just bite the bullet and use a loop - ToDictionary does this behind the scenes anyway.
However, if you really dislike looping, then try something like this:
var keyValuePairs = from string key in lst.Distinct() select new KeyValuePair<string, int>(key,
lst.Count(
(string str) => (key == str))
);
That should provide you with a list of KeyValuePairs. I'm not certain how to get those KeyValuePairs into a Dictionary, (maybe a cast or AddRange?) but it's a start.
Note: There may be syntax errors in that snippet; I wrote that in the browser, so the compiler hasn't done any error checking
Between the idea
And the reality
Between the motion
And the act
Falls the Shadow
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thankssssssssssssss
As you help people. God will help you..
Thanks again..
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You have no choice but to use a loop. Even if you wrote your own Dictionary class to handle incrementing the value every time the same string gets added.
You'll either be using a loop inside your custom Dictionary as you go through each item passed in by some kind of AddRange method, or you'll be using a loop to iterate over a list of strings to pass to your custom Dictionary's Add method.
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Hey if someone could help me to understand how to fix this issue I am having I would greatly appreciate it.
Problem:
I am developing a c# application, in doing so the I am currently using application properties because I could not figure out how to use the xml method of storing and retrieving settings. Ultimately I would like to use my own xml file and not use system properties but I am in need of some training for that. I can be contacted on skype at mgassist or jollymansart. Back to the issue. I need to be able to programmaticlly update the property setting. I do not know how to programmaticlly update the system property. mgeorge@peerassistllc.com.
Here is what the xml file looks like from the application settings:
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<configSections>
<sectionGroup name="applicationSettings" type="System.Configuration.ApplicationSettingsGroup, System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" >
<section name="PeerAssistLoader.Properties.Settings" type="System.Configuration.ClientSettingsSection, System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />
</sectionGroup>
<sectionGroup name="userSettings" type="System.Configuration.UserSettingsGroup, System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" >
<section name="PeerAssistLoader.Properties.Settings" type="System.Configuration.ClientSettingsSection, System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" allowExeDefinition="MachineToLocalUser" requirePermission="false" />
</sectionGroup>
</configSections>
<connectionStrings />
<applicationSettings>
<PeerAssistLoader.Properties.Settings>
<setting name="AppLoaderConnectionString" serializeAs="String">
<value>Password=zephyr;Persist Security Info=True;User ID=mike;Initial Catalog=AppLoader;Data Source=PA-DEVplatform1\sql2005</value>
</setting>
<setting name="DefaultWSPath" serializeAs="String">
<value>Please Place the default Workstation Path</value>
</setting>
<setting name="DefaultMSAccess" serializeAs="String">
<value>C:\Program Files\Microsoft Office\Office12\msaccess.exe</value>
</setting>
</PeerAssistLoader.Properties.Settings>
</applicationSettings>
<userSettings>
<PeerAssistLoader.Properties.Settings>
<setting name="DefaultSNVPath" serializeAs="String">
<value>Please Place the default Server Path</value>
</setting>
</PeerAssistLoader.Properties.Settings>
</userSettings>
</configuration>
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(tested and used a lot.. I'm just too lazy to make an article about it...)
<br />
public class ConfigFile<br />
{<br />
#region GetDefaultPath(..)<br />
<br />
public static string GetDefaultPath()<br />
{<br />
return GetDefaultPath(ConfigurationFolder.LocalApplicationData, null);<br />
}<br />
public static string GetDefaultPath(ConfigurationFolder folder)<br />
{<br />
return GetDefaultPath(folder, null);<br />
}<br />
public static string GetDefaultPath(ConfigurationFolder folder, string name)<br />
{<br />
string dir = AppInfo.GetDataDirectory(folder);<br />
if (string.IsNullOrEmpty(name))<br />
name = AppInfo.AppName;<br />
return Path.Combine(dir, string.Format("{0}.config", name.PathSafe()));<br />
}<br />
<br />
#endregion<br />
<br />
#region GetShared config files<br />
<br />
public static ConfigFile GetShared()<br />
{<br />
return GetShared(GetDefaultPath());<br />
}<br />
public static ConfigFile GetShared(ConfigurationFolder folder)<br />
{<br />
return GetShared(GetDefaultPath(folder));<br />
}<br />
public static ConfigFile GetShared(ConfigurationFolder folder, string name)<br />
{<br />
return GetShared(GetDefaultPath(folder, name));<br />
}<br />
public static ConfigFile GetShared(string path)<br />
{<br />
lock (configFiles)<br />
{<br />
ConfigFile result;<br />
if (!configFiles.TryGetValue(path, out result))<br />
{<br />
result = new ConfigFile(path);<br />
configFiles[path] = result;<br />
}<br />
return result;<br />
}<br />
}<br />
<br />
static Dictionary<string, ConfigFile> configFiles = new Dictionary<string, ConfigFile>();<br />
<br />
public static void SaveAll()<br />
{<br />
lock (configFiles)<br />
{<br />
foreach (var cf in configFiles.Values)<br />
cf.Save();<br />
}<br />
}<br />
<br />
#endregion<br />
<br />
#region instance methods: Save(), Reload(), GetSection<T>()<br />
<br />
XDict config = new XDict();<br />
<br />
public ConfigFile(string path)<br />
{<br />
FilePath = path;<br />
if (string.IsNullOrEmpty(path))<br />
throw new ArgumentNullException("path");<br />
Reload();<br />
}<br />
<br />
public string FilePath { get; private set; }<br />
<br />
public void Save()<br />
{<br />
string dir = Path.GetDirectoryName(FilePath);<br />
if (!Directory.Exists(dir))<br />
Directory.CreateDirectory(dir);<br />
<br />
XDocument doc = new XDocument(config.ToXNode());<br />
doc.Save(FilePath);<br />
}<br />
<br />
public void Reload()<br />
{<br />
if (File.Exists(FilePath))<br />
try<br />
{<br />
XDocument doc = XDocument.Load(FilePath);<br />
XElement xdict = doc.Root;<br />
config = new XDict();<br />
if (xdict != null)<br />
config.FromXNode(xdict);<br />
}<br />
catch (InvalidOperationException) { }<br />
catch (XmlException) { }<br />
}<br />
<br />
public XDict GetSection<T>()<br />
{<br />
string key = typeof(T).FullName;<br />
XDict section = config.Get<XDict>(key);<br />
if (section == null)<br />
{<br />
section = new XDict();<br />
config[key] = section;<br />
}<br />
return section;<br />
}<br />
<br />
#endregion<br />
}<br />
<br />
public interface IXObject : IXmlSerializable<br />
{<br />
XNode ToXNode();<br />
void FromXNode(XNode node);<br />
}<br />
<br />
public class XValue : IXObject<br />
{<br />
public XValue() { }<br />
public XValue(string s) { StringValue = s; }<br />
<br />
public string StringValue { get; set; }<br />
<br />
public override string ToString()<br />
{<br />
return StringValue;<br />
}<br />
<br />
#region Strongly Typed Value<br />
<br />
public T Get<T>()<br />
{<br />
return Get<T>(default(T));<br />
}<br />
public T Get<T>(T defaultVal)<br />
{<br />
T ret;<br />
if (!string.IsNullOrEmpty(StringValue))<br />
{<br />
if (Converter.TryGetTValue<T>(StringValue, out ret))<br />
return ret;<br />
StringValue = null;<br />
}<br />
return defaultVal;<br />
}<br />
<br />
public void Set<T>(T val)<br />
{<br />
Set<T>(val, default(T));<br />
}<br />
public void Set<T>(T val, T defaultVal)<br />
{<br />
if (Equals(val, defaultVal))<br />
{<br />
StringValue = null;<br />
}<br />
else<br />
{<br />
string ret;<br />
if (Converter.TryGetStringValue<T>(val, out ret))<br />
StringValue = ret;<br />
}<br />
}<br />
<br />
#endregion<br />
<br />
#region static IXObject Create(XNode node)<br />
<br />
internal static IXObject Create(XNode node)<br />
{<br />
if (node == null)<br />
return null;<br />
if (node is XText)<br />
{<br />
XValue val = new XValue();<br />
val.FromXNode(node);<br />
return val;<br />
}<br />
else if (node is XElement)<br />
{<br />
XElement xe = (XElement)node;<br />
switch (xe.Name.LocalName)<br />
{<br />
case "list":<br />
XList xl = new XList();<br />
xl.FromXNode(xe);<br />
return xl;<br />
case "dictionary":<br />
XDict xd = new XDict();<br />
xd.FromXNode(xe);<br />
return xd;<br />
}<br />
}<br />
return null;<br />
}<br />
<br />
#endregion<br />
<br />
#region IXObject Members<br />
<br />
public XNode ToXNode()<br />
{<br />
var s = StringValue;<br />
if (s == null)<br />
s = "";<br />
return new XText(s);<br />
}<br />
<br />
public void FromXNode(XNode node)<br />
{<br />
XText t = node as XText;<br />
if (t != null)<br />
StringValue = t.Value;<br />
}<br />
<br />
#endregion<br />
<br />
#region IXmlSerializable Members<br />
<br />
public XmlSchema GetSchema()<br />
{<br />
return null;<br />
}<br />
<br />
public void ReadXml(XmlReader reader)<br />
{<br />
try<br />
{<br />
reader.Read();<br />
XNode node = XNode.ReadFrom(reader);<br />
FromXNode(node);<br />
}<br />
catch (InvalidOperationException) { }<br />
catch (XmlException) { }<br />
}<br />
<br />
public void WriteXml(XmlWriter writer)<br />
{<br />
ToXNode().WriteTo(writer);<br />
}<br />
<br />
#endregion<br />
}<br />
<br />
public class XList : List<IXObject>, IXObject<br />
{<br />
public override string ToString()<br />
{<br />
StringBuilder sb = new StringBuilder("[");<br />
for (int i = 0; i < 10 && i < Count; i++)<br />
{<br />
if (i > 0)<br />
sb.Append(", ");<br />
sb.Append(this[i]);<br />
}<br />
if (Count > 9)<br />
sb.Append(", ...");<br />
sb.Append("]");<br />
return sb.ToString(); ;<br />
}<br />
<br />
#region IXObject Members<br />
<br />
public XNode ToXNode()<br />
{<br />
XElement top = new XElement("list");<br />
foreach (var item in this)<br />
{<br />
top.Add(new XElement("item", item.ToXNode()));<br />
}<br />
return top;<br />
}<br />
<br />
public void FromXNode(XNode node)<br />
{<br />
XElement xe = node as XElement;<br />
if (xe == null || xe.Name != "list")<br />
return;<br />
foreach (XElement item in xe.Elements("item"))<br />
{<br />
XNode itemNode = item.FirstNode;<br />
Add(XValue.Create(itemNode));<br />
}<br />
}<br />
<br />
#endregion<br />
<br />
#region IXmlSerializable Members<br />
<br />
public XmlSchema GetSchema()<br />
{<br />
return null;<br />
}<br />
<br />
public void ReadXml(XmlReader reader)<br />
{<br />
try<br />
{<br />
reader.Read();<br />
XNode node = XNode.ReadFrom(reader);<br />
FromXNode(node);<br />
}<br />
catch (InvalidOperationException) { }<br />
catch (XmlException) { }<br />
}<br />
<br />
public void WriteXml(XmlWriter writer)<br />
{<br />
ToXNode().WriteTo(writer);<br />
}<br />
<br />
#endregion<br />
}<br />
public class XDict : Dictionary<string, IXObject>, IXObject<br />
{<br />
public override string ToString()<br />
{<br />
StringBuilder sb = new StringBuilder("{");<br />
int i = 0;<br />
foreach (var item in this)<br />
{<br />
if (i > 0)<br />
sb.Append(", ");<br />
i++;<br />
sb.Append(item.Key);<br />
sb.Append(": ");<br />
sb.Append(item.Value);<br />
}<br />
if (Count > 9)<br />
sb.Append(", ...");<br />
sb.Append("}");<br />
return sb.ToString(); ;<br />
}<br />
<br />
public new IXObject this[string key]<br />
{<br />
get<br />
{<br />
IXObject result;<br />
TryGetValue(key, out result);<br />
return result;<br />
}<br />
set<br />
{<br />
if (value == null)<br />
Remove(key);<br />
else<br />
base[key] = value;<br />
}<br />
}<br />
<br />
#region Strongly Typed Helper<br />
<br />
public T Get<T>(string key)<br />
{<br />
return Get<T>(key, default(T));<br />
}<br />
public T Get<T>(string key, T defaultVal)<br />
{<br />
IXObject xo;<br />
TryGetValue(key, out xo);<br />
if (typeof(IXObject).IsAssignableFrom(typeof(T)))<br />
{<br />
if (xo is T && xo != null)<br />
return (T)xo;<br />
return defaultVal;<br />
}<br />
<br />
XValue xv = xo as XValue;<br />
T ret;<br />
if (xv != null && !string.IsNullOrEmpty(xv.StringValue))<br />
{<br />
if (Converter.TryGetTValue<T>(xv.StringValue, out ret))<br />
return ret;<br />
}<br />
Remove(key);<br />
return defaultVal;<br />
}<br />
<br />
public void Set<T>(string key, T val)<br />
{<br />
Set<T>(key, val, default(T));<br />
}<br />
public void Set<T>(string key, T val, T defaultVal)<br />
{<br />
if (typeof(IXObject).IsAssignableFrom(typeof(T)))<br />
{<br />
IXObject xo = val != null ? (IXObject)val : (IXObject)defaultVal;<br />
this[key] = xo;<br />
return;<br />
}<br />
<br />
XValue xval;<br />
if (Equals(val, defaultVal))<br />
{<br />
xval = null;<br />
}<br />
else<br />
{<br />
string ret;<br />
if (Converter.TryGetStringValue<T>(val, out ret))<br />
xval = new XValue(ret);<br />
else<br />
xval = null;<br />
}<br />
if (xval == null)<br />
Remove(key);<br />
else<br />
this[key] = xval;<br />
}<br />
<br />
#endregion<br />
<br />
#region IXObject Members<br />
<br />
public XNode ToXNode()<br />
{<br />
XElement top = new XElement("dictionary");<br />
foreach (var item in this.Keys)<br />
{<br />
XElement xitem = new XElement("item", this[item].ToXNode());<br />
xitem.Add(new XAttribute("key", item));<br />
top.Add(xitem);<br />
}<br />
return top;<br />
}<br />
<br />
public void FromXNode(XNode node)<br />
{<br />
XElement xe = node as XElement;<br />
if (xe == null || xe.Name != "dictionary")<br />
return;<br />
foreach (XElement item in xe.Elements("item"))<br />
{<br />
string name = item.Attribute("key").Value;<br />
XNode itemNode = item.FirstNode;<br />
this[name] = XValue.Create(itemNode);<br />
}<br />
}<br />
<br />
#endregion<br />
<br />
#region IXmlSerializable Members<br />
<br />
public XmlSchema GetSchema()<br />
{<br />
return null;<br />
}<br />
<br />
public void ReadXml(XmlReader reader)<br />
{<br />
try<br />
{<br />
reader.Read();<br />
XNode node = XNode.ReadFrom(reader);<br />
FromXNode(node);<br />
}<br />
catch (InvalidOperationException) { }<br />
catch (XmlException) { }<br />
}<br />
<br />
public void WriteXml(XmlWriter writer)<br />
{<br />
ToXNode().WriteTo(writer);<br />
}<br />
<br />
#endregion<br />
}<br />
<br />
A train station is where the train stops. A bus station is where the bus stops. On my desk, I have a work station....
_________________________________________________________
My programs never have bugs, they just develop random features.
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That smells like an Article, to me!
Henry Minute
Do not read medical books! You could die of a misprint. - Mark Twain
Girl: (staring) "Why do you need an icy cucumber?"
“I want to report a fraud. The government is lying to us all.”
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Ho.. ok, well I might do an extra effort this week end! 
Caught in my own trap! 
A train station is where the train stops. A bus station is where the bus stops. On my desk, I have a work station....
_________________________________________________________
My programs never have bugs, they just develop random features.
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Thanks a lot that was very helpful!
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Good!
Now I should write an article about that!
A train station is where the train stops. A bus station is where the bus stops. On my desk, I have a work station....
_________________________________________________________
My programs never have bugs, they just develop random features.
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not able to view the form controls when thread is running
can any one help...plss
m using thread and timer
any problem in using timer or thread
This code was posted by me...
modified on Friday, July 31, 2009 8:57 AM
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Hi
i created a web service to load some information from sql server 2005 database, it works good but it has very low speed to return data, wheras sql server load data without overhead. i think the decreasing performance occures in while loop, here is my code :
[WebMethod]
public List<InputOutput> GetAllInputOuts()
{
List<InputOutput> list = new List<InputOutput>();
using (System.Data.SqlClient.SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["IOXPConnectionString"].ConnectionString))
{
using (SqlCommand cmd = con.CreateCommand())
{
cmd.CommandText = "select * from vLinkToDataSource";
SqlDataReader dr = null;
if (con.State != ConnectionState.Open)
con.Open();
dr = cmd.ExecuteReader();
while (dr.Read())
{
InputOutput io = new InputOutput();
io.Code = dr.GetInt32(2);
io.Name = dr.GetString(1);
io.Family = dr.GetString(0);
io.DateInput = dr.GetString(3);
io.TimeInput = dr.GetString(4);
io.DateOutput = dr.GetString(5);
io.TimeOutput = dr.GetString(6);
list.Add(io);
}
}
}
return list;
}
how to improve the performance ?
Note 1 : the sql server 2005 return results good.
Note 2 : almost 17000 records exists in database.
Note 3 : beacuse i want to use this web Service in sharepoint, i must return result as List<T>.
Any help would be great appreciated
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So, you're returning all 17,000 records, adding them one at a time to the List<t>, then having the Web Method serialize the entire List<t> (will probably take a while), tranferring what amounts to megabytes of XML text, then having the client deserialize the entire list (will probably take a while, again)??
I think you biggest problem is trying to handle 17,000 records all at once. I'd probably want to limit the data I return from the database and reduce the dataset to only the data that is absolutely necessary at a certain point in time. What are you doing with all 17,000 records that you need to transfer them all?
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Hi Dave
my goal is load all data into sharepoint via bussiness data catalog (bdc), it's finder method, then write another webMethod to find only data which matched to criteria, It's specific finder method.
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Well, then I'd probably look at a caching solution on the Sharepoint side if your data doesn't change very often, or if your SQL Server is 2005 or above, some kind of solution to return the query as your XML dataset and returning that to the client.
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Thanks Dave
but, what's XML dataset ?
can u give me an example ?
thanks
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I don't have any examples, but you can start your own research into it by Googling for "SELECT FOR XML".
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I am experiencing difficulty trying to make a trackbar scroll when the middle mouse button/ball is clicked and scrolled.
I need the mouse scroll wheel to scroll up and down when it is clicked and reset the value to the middle when realised.
Does anyone know how this can be done.
Thanx George
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I have tried this:
private void trackBar1_Scroll_1(object sender, MouseEventArgs m)
{
if (m.Button == MouseButtons.Middle)
{
label1.Text = trackBar1.Value.ToString();
}
}
but dont know if it will work as havent got it to compile because its complaining about the delegate
this.trackBar1.Scroll += new System.EventHandler(this.trackBar1_Scroll_1);
I dont know how to change it, it works with eventArgs but i put in mouseEventArgs which i need and it does not like it.
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Hi,
you can't just change the partameter types; Scroll gives an EventArgs, not a MouseEventArgs.
you are aware of the Control.MouseWheel event? That one offers a MouseEventArgs.
Luc Pattyn [Forum Guidelines] [My Articles]
The quality and detail of your question reflects on the effectiveness of the help you are likely to get.
Show formatted code inside PRE tags, and give clear symptoms when describing a problem.
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Thanks for that. You just answered my question too! lol  
2 answers in 1!
Regards,
Jason Pezzimenti.
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