ADO.NET :: Creating Dynamic Expressions For Lambda IQueryable Expressions?
Sep 30, 2010
I have a ListBox that contains userNames which is inputted by a user during run time. This number of items in the ListBox is dependent on the user's input. These userNames will then be used in a Lambda expression like this:
var vHandleResult = vHandleResult.Where(a => a.UserName.Contains("userName"));
This works fine when there is only 1 user in the ListBox but doesn't produce the correct results when there are multiple items in the listBox. I tried manually creating the expression which should be written as this:
I tried forming the "a.UserName.Contains("userName") expression as a string which is dependent on the number of the items (using foreach) and then just plug in the resulting string in the expression but it seems that it doesnt accept string as an expression.
I'm debugging some tricky generic List-based code in VS 2010 - lots of heirarchy-processing etc.. Of course lambda expressions and anonymous methods aren't permitted within the immediates window and I can't be doing with stepping thru the code in the usual way as I'm still trying to get my head around the hierarchies ...Can anyone suggest a workaround or an alternative tool?P.S. An aside - I can't seem to find a visual studio 2010 tag?
I have got a datatable which contains many columns in which three are main:
hotelid dshotelid hotelname
Some hotels contain only dshotelid, some contains only hotelid and some contain both dshotelid and hotelid.
I need sort in such way so that those hotels who got both dshotelid and hotelid should be on top and then those hotels who have got only dshotelid and at last those hotels who have got only hotelid...
I am tring to calculate the expressions then my problem is when give in double values it did not working and error with undefined symbol(.). I am using one class file for evaluting the expression.
ex: 10/2+58*7-69 //valid 5655/854*564-552+64/42+215 //valid but 52.36+56.2 // Not valid
Above are the examples for evaluting method, how can evalute double values give me sample code
if there are two consecutive apostrophe or two consecutive hyphens or two consecutive comma or two consecutive spaces or two consecutive periods or two consecutive periods..I want to display those particular error.
and One more thing is if there are any of the above combinations like apostrophe+hyphen or apostrophe+space or hyphen+space, I want to throw that specific error.
I think it can be solved by Regular expressions but maby I'm wrong. I upload a .html file which is saved from a webbrowser. I read the stream and with Stringbuilder I make a string of it.But now I want to have only the data which is in this div:
I have two the below regular expressions for a textbox , to validate.
^(([01]?dd?|2[0-4]d|25[0-5]).){3}([01]?dd?|25[0-5]|2[0-4]d)$ - Validation Expression For IP Address ^(([a-zA-Z0-9]|[a-zA-Z0-9][a-zA-Z0-9-]*[a-zA-Z0-9]).)*([A-Za-z]|[A-Za-z][A-Za-z0-9-]*[A-Za-z0-9])$ - Validation Expression for Host name
I want to use both these for the same textbox, It should fullfill either of these conditions. What should I do so as to satisfy my condition.
Is it possible to design a page in Expressions Web and then use it in Visual Studio Presently, I am using an asp.net master page in Visual Studio with functionality from the VS tool box (navigation tree, login etc). These work fine but they are not very pretty. How can I keep all the functionality that Visual studio offers (I will be adding an SQL database) but have it looking better than the drag and drop tools in VS. Is it possible or not to connect an Expressions Web Master page easily, so it will drive the site already built in VS - but have a more attractive GUI?
Or, is there something that I am missing in Visual Studio - can I edit the drag and drop tools in there to build a GUI with a Microsoft feel and look?
I am trying to search titles in this pattern a text. the titles are unknown and sometimes it contains special characters '(' and ')'.... when this is happens the only way to make the match correct is by replace ')' by ')' . is there a way ignoring this replacment? and if not, what are the complete meta(special) characters?
I'm pretty sure this is something super easy, but how do i access a resource that is in a separate project using the expression syntax? I thought it would be like so:
I want a limited amount of html tags for the user to be able to put in my form and by looking at the posts, regular expressions seem to be the way forward. I don't want to use javascript or 3rd party as this is for an assignment at university.
The examples I have found seem to be set out differently than mine with using asp id identifiers whereas my code below is set out differently so I am unsure if I can use these examples.
I am building a forum and I want to be able to use simple square bracket tags to allow users to format text. I am currently accomplishing this by parsing the string and looking for the tags. It's very tedious, especially when I run into a tag like this [URL]. Having to parse the attribute, and the value, and make sure it has proper opening and closing tags is kind of a pain and seems silly. I know how powerful regular expressions are but I'm not good at them and they frustrate me to no end. I think an example would get me started. Just a regex for finding tags like [b]bolded text[/b] and tags with attributes like the link
I applied regular expression validator on date of birth and Missing date for a missing person. the missing date should be greater than the date of birth . I applied compare vallidator but it is not working properly. it comparing day of date of birth with day of missing date, both months and years...
I created a GridView in code with a DataTable as its data source which worked fine. I have now moved the GridView creation into a .ascx file to make it easier to format.
For some reason this has started triggering the HttpParseException: Databinding expressions are only supported on objects that have a DataBinding event. System.Web.UI.WebControls.HyperLinkField Original code: // Set up columns for datagrid var boundField = new HyperLinkField [code]...
return from c in db.TBLcharacters join o in db.TBLjobs on c.char_job equals o.job_title orderby c.char_lastname descending select c;
The goal is to print out the job title from the seperate table when I list the names of the Employees. So in the final formatting on the view it would be John Doe [Janitor] (or something similiar)
But when I make the build I get the following error:
The type of one of the expressions in the join clause is incorrect. Type inference failed in the call to 'Join'.
What I find wierd is cjar_job and job_title are both varchars so the type is the same.
I am getting ready to just write my own, but I have a need for some regular expressions that will validate strings to make sure they are in an acceptable format to be inserted/updated into a database field. I figure it may just be to find a list of them someone has already posted somewhere and just use those.
If you still clicked this after seeing the title, you are probably like me and sometimes code just for fun. So, that's the spirit of this; all new approaches that solve this will be marked as answer.I have a template that I can't imagine ever using again, but use 5 times on a page. I wanted to DRY up my page a little:
[Code]....
While doing this, I realized that Lambdas confuse me - I had the feeling there was a much simpler way to code it.
