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void GetNameChangedToProtectTheInnocent()
{
try
{
...
}
catch
{
}
}
There you go - not empty! Written by yours truly, only 10mins ago  . In my defence, it's important that the site doesn't throw errors and this is what the rest of the site does. 
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Fair enough, but it should at least be logged for investigation. If it's unimportant and not worth logging then it should be handled in code so the exception never arises.
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I was being a bit (OK, very) toungue-in-cheek. 99.99% of the time I really wouldn't do this. In this case he exception is very unimportant, for various reasons I'd have to write my own logging infrastructure (which would take longer than the rest of the change, and my code is slated for replacement by an MVC app very soon) and I can't handle in code as the try-block is calling out to an asmx service and I'm guarding against technical errors. I could, I suppose tighten which errors are being caught.
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Actually, my catch block had a lot in it. It was just not included in my post!
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In Visual Studio, You can enable breaking at an exception even when it is caught and handled. This will be very useful during debugging.
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I wonder if it's my data. My strings are "00", "55", "20", "00", and "99".
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plz i need link of proggrams in c# concern with panorama images (stitching image)
help me
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Please read the top message on this board ("How to ask a question") otherwise people will down-vote your question. Asking for code like this is unlikely to get a response as we are pretty much all volunteers here. Everyone will assume you have tried nothing even if, in reality, you have spent hours figuring it out - we can't tell. Stitching photos isn't a facile task, and unlikely to be answered in a forum post.
It is better to ask a specific question, outlining what you have tried to achieve, or, what the exact problem is you are having getting started. Oh and a title of "hello isn't very descriptive"
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See this[^] excellent article that uses the Accord and AForge frameworks.
/ravi
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Hi,
I want to know how to store data in excel using VC# 2010.
i.e.) i will enter the values in UI say name and age, and i want those values to reflect in my Excel sheet without using any database.
Can anyone please share me the code for this.
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Anusha Sridhar wrote: Can anyone please share me the code for this.
You are asking if anyone can write the code for you. Create a UI, do a quick Google, try something (any tutorial or example will do) and report back if you're stuck.
Alternatively, you could cough up a nice amount for WarChild, and I might be tempted to copy/paste one of the tutorials from Google here.
Bastard Programmer from Hell 
if you can't read my code, try converting it here[^]
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Use Office Open Xml SDK to achieve this.
Refer this thread. Create a DataTable object from your UI code and use the rest of the code in the solution.
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I use ADO.net with the OleDb provider for Jet/Ace
See also: http://connectionstrings.com/excel[^]
and then it's simple SQL:
create table Test (ID number,Name string)
insert into Test VALUES ('1','Alice')
insert into Test VALUES ('2','Bob')
SELECT * FROM Test
Etc.
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Hello all,
I'm trying to download a file from a folder on the server but I don't know how to parse the path inside of the HREF attribute of the anchor tage. I'm trying to modify the following code to be used with HTML anchor tag:
protected void Page_PreRender(object sender, EventArgs e)
{
DataTable dt = new DataTable("INFO");
dt.Columns.Add("url", typeof(string));
string[] fileEntries = Directory.GetFiles(Server.MapPath("~/Documents/"));
dt.Rows.Add("~/Documents/" + Path.GetFileName(fileName));
grid.DataSource = dt;
grid.DataBind();
}
I wanted to do something like the following on my Page.aspx file:
<a href="~/Documents/" + Path.GetFileName(fileName)"> DOWNLOAD </a>
However, the above cannot be done. Please help me find and alternative, thanks for your help.
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Could you please ask questions about ASP.NET in the ASP.NET forum. That's where you will find ASP.NET experts.
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Hi, this thread represents a summary of what I have learned since starting the thread [^] on this forum: re use of dynamic to allow direct access to a 'value without the need for casting that 'value (currently an 'object) to its appropriate type.
In the code below I compare and contrast for three different types of .NET types, KeyValuePairs, Tuples, and List<dynamic> what using 'dynamic enables compared to using 'object in the constructor of these types.
I am particularly interested in the reactions of Martijn Kok and DaveyM69, who were kind enough to post interesting comments on the original thread: I believe, that what I demonstrate here does change the implications of one comment by Martijn Kok (as I understood that comment: and my understanding may well be in error).
Of course, comments would be welcome about use of 'dynamic in general, and the potential "overhead" of using a Type like List<dynamic> !
I would also be interested in knowing your opinion if there is enough material here for a "Tip/Trick."
thanks, Bill
// KeyValuePair declarations
private KeyValuePair<Type, object> Kvp1 = new KeyValuePair<Type, object> (typeof(int), 199);
private KeyValuePair<Type, dynamic> Kvp2 = new KeyValuePair<Type, dynamic>(typeof(int), 199);
// Tuple declarations
private Tuple<Type, object> twoTuple1 = new Tuple<Type, object>(typeof(int), 199);
private Tuple<Type, dynamic> twoTuple2 = new Tuple<Type, dynamic>(typeof(int), 199);
// List<dynamic> declaration
private List<dynamic> dyList = new List<dynamic>();
// method that demonstrates use of declared objects above
private void TestDynamicVsNonDynamic()
{
// using KeyValuePair
//int a = Kvp1.Value + 1; // will not compile
int b = Kvp2.Value + 1; // will compile, give expected result
// using Tuple
//int x = twoTuple1.Item2 + 1; // will not compile
int y = twoTuple2.Item2 + 1; // will compile, give expected result
// using List<dynamic>
dyList.Add(199); // will compile
dyList.Add(new TextBox{Text = "some text&"});
int z = dyList[0] + 1; // will compile, give expected result
dyList[1].Text += " ... blah, blah blah";
string s = dyList[1].Text; // will compile, give expected result
Type dyList1Type = dyList[1].GetType(); // returns expected Type: TextBox
}
"If you shoot at mimes, should you use a silencer ?" Stephen Wright
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Hi Bill,
The results you show are exactly what I would expect. Using object, although the Type is readily available, to use it as that type (using the + operator in your example) requires a cast:
int a = ((int)(Kvp1.Value)) + 1;
dynamic does not have this limitation as Kvp1.Value in your example will be dynamically resolved to an int at runtime and therefore has all the functionality of that struct.
This is the primary (only?) advantage of dynamic over object - using object can require casts all over the place! What the overhead is of dynamic (if any) I don't know as I've never found the need to use it in my own code.
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Thanks, DaveyM,
What I remain puzzled by is that if I use, for example, a KeyValuePair<Type,object>: like this:
private KeyValuePair<Type, object> kvpTO;
private void messWith_kvpTO()
{
kvpTO = new KeyValuePair<Type, object>(typeof(string), "some text");
Type workingType = kvpTO.Key;
// workingType now contains:
// [System.RuntimeType] = {Name = "String" FullName = "System.String"}
// fail "cannot recognize kvpTO"
//string kvpString = (workingType) kvpTO.Value;
// fail "cannot recognize kvpTO"
//string kvpString = kvpTO.Value as workingType;
}I cannot find any way to use the valid run-time Type to convert the "string" from an object to a string in a generic way: where the Type could any valid Type, and I do not know what that Type is at run-time.
Have any idea how to do that ?
It was my inability to use the 'Type in the 'KeyValuePair to do "casting" from object: that led me to using 'dynamic.
best, Bill
"If you shoot at mimes, should you use a silencer ?" Stephen Wright
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As you're storing the Type and the object in one pair so it's guaranteed to be a valid cast, you could use Convert.ChangeType[^] to do this:
string kvpString = Convert.ChangeType(kvpTO.Value, kvpTO.Key);
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Hi Dave,
string kvpString = Convert.ChangeType(kvpTO.Value, kvpTO.Key); I am afraid that one will not work: "Error Cannot implicitly convert type 'object' to 'string'. An explicit conversion exists (are you missing a cast?)"
You'll note the examples on the MSDN page you linked to all use a specific cast on the result returned by calling Convert.ChangeType:
Double d = -2.345;
int i = (int)Convert.ChangeType(d, typeof(int));
Console.WriteLine(&amp;quot;The double value {0} when converted to an int becomes {1}&amp;quot;, d, i);
string s = &amp;quot;12/12/98&amp;quot;;
DateTime dt = (DateTime)Convert.ChangeType(s, typeof(DateTime));
"If you shoot at mimes, should you use a silencer ?" Stephen Wright
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OK, looking at generics this is getting a bit 'hackish', but a few moments thought and this may work:
public static T GetValue<T>(KeyValuePair<Type, object> keyValuePair)
{
return (T)Convert.ChangeType(keyValuePair.Value, typeof(T));
}
Test:
KeyValuePair<Type, object> keyValuePair = MakeKeyValuePair(123.58);
int i = GetValue<int>(keyValuePair) + 1;
Console.WriteLine(i);
edit: forgot this method!:
public static KeyValuePair<Type, object> MakeKeyValuePair(object obj)
{
return new KeyValuePair<Type, object>(obj.GetType(), obj);
}
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Hi DaveyM69,
Yes, this will work, but note that you are required to know what Type you want returned, and specify it in the call to GetValue<T> : to me that is really the same requirement as having to do an explicit cast on the result of Convert.ChangeType, just more elegant  .
Appreciate your comments, but, so far, still convinced that 'dynamic adds something unique to this (albeit esoteric) area of .NET Type conversion we are exploring.
... edit ...
Note that this code, similar to yours in structure, would work without the need for type specification:
public static dynamic x_GetValue<T>(KeyValuePair<Type, object> keyValuePair)
{
return Convert.ChangeType(keyValuePair.Value, typeof(T));
}
string kvpString = x_GetValue<dynamic>(kvpTO);
var kvpString = x_GetValue<dynamic>(kvpTO);
kvpString += "... even more text";
Console.WriteLine(kvpString.GetType() + " : " + kvpString); However, I think a possible valid "challenge" to using 'dynamic, compared to other strategies that return 'object: is that the programmer is still going to need to know, in all cases, what type of value will be returned here ... unless the programmer implements some kind of switch/case statement to take action based on the run-time type.
I'm trying to imagine a real-world use case where using 'dynamic, in the ways explored on this thread, would be really required, and "best practice:" I admit to failing to do that ... so far.
Would it benefit others on CP, to write up this usage of 'dynamic as a tip-trick ? Not sure !
... end edit ...
best, Bill
"If you shoot at mimes, should you use a silencer ?" Stephen Wright
modified 29-Aug-12 0:21am.
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BillWoodruff wrote: the programmer is still going to need to know, in all cases, what type of value will be returned
That is the issue. Regardless of object, dynamic, var or whatever, to use the return value for anything you're gonna need to know what it is.
BillWoodruff wrote: Would it benefit others on CP
Yes, if you can find a use case
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in trying to make better use of the using statement i came across some syntax i haven't been able to sort out.
basic MailMessage syntax sets properties separated by commas, like this:
MailMessage message = new MailMessage()
{
From = new MailAddress("mailx@website.com", "it's me."),
Subject = subject,
Body = userMessage
};
...
message.Dispose();
if i add a using statement, i haven't found a way of setting those properties with the same syntax. i've had to do it "long-hand", with message.From, message.Subject, etc.:
using ( MailMessage message = new MailMessage() )
{
message.From = new MailAddress("mailx@website.com", "it's me.");
message.Subject = subject;
message.Body = userMessage;
...
mailClient.Send(message);
}
is there a way of setting the properties in a comma-separated way with a using statement?
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