Forms Data Controls :: How To Get Fields Calculated Before They Get Displayed
Jul 27, 2010
I'm a college intern at a small software company. I'm a novice when it comes to ASP.net and Expression Web, so sorry if these are obvious questions.
1. After figuring out how to get fields calculated before they get displayed (did this with SQL), I need to find a way to put certain characters before the output in the fields. I'm fairly certain this is done with a template field, but I have no idea how to touch those without making them blow up.
2. I would also like to have color in the GridViews rows or cells depending on a value returned from the database. Again, I think this would be done with template fields.
3. Thirdly, I need to be able to limit the characters in a few cells. I've searched and found some answers with this, but still Template fields go right over my head.
My gridview displays fields from a table and allows for edit, delete and insert. I need to add a column with a derived field which will be calculated every time the user is either entering a new row or editing the value of the weight field which is one of the fields of the gridview. This calculation is done in the fly and won't be saved in the database.
I have a GridView bound to an ObjectDataSource. Most of the columns are directly databound, however one column is not - it's value is determined in code. The value is being calculated correctly at the RowDataBound event, however when there is more than one data row in the GridView, the calculated fields for all of the rows is blank, but the top row displays the bottom row's calculated field
I need a form that displays three columns drawn directly from a database (no problems here) as well as two fields that require some complex calculations. Not only am I lost as to how to incorporate the calculations into the control, I don't know exactly how to write the calculations. I am working in Visual Web Developer 2008 with Vb.NET.
The first of the two fields should take the sum of all payments made by a given customer and divide it by a DailyMembershipRate, returning a DaysPaid variable. It should take this variable and a CustomerSince field for that particular customer and calculate a PaidThrough field.
The second of the two columns similarly requires the DaysPaid variable described above. It should subtract the CustomerSince field from the current date and return the value in days, giving a MembershipDays variable. Finally, it should subtract MembershipDays from the DaysPaid variable, again returning a value in days, and then multiply this by the DailyRate value for a Credit/Deficit field.
I realize this is a lot, but I haven't been able to find any documentation either online or in VWD or ASP.NET texts on this topic. I could really use some fellow user input.
Split off from http://forums.asp.net/t/1595139.aspx:
I have an additional column called 'KPI %' in my gridview that calculates the percentage of two template fields and thus I cannot use the sortexpression on it. How can I sort the contents of the 'KPI %' column in ASC or DESC format?
I have 2 amount columns (Amount and TotAmount) in my gridview. In Amount column data comes from database. I want to display the total of amounts in Amount column in my TotAmount column (So there would be just one value in TotAmount column irrespective of the number of columns in Amount column). How can I do this.
Is there a way to Sort a Gridview by a Calculated Column? I have a gridview with template fields using lablels and a linq datasource. Those columns sort just fine. I can not get the Calculated column to sort, because there is no sort expression to use...
I have tried several different approaches .SOMEONE PLEASE sow me how to sort on template field with a calculated value.Basically i have half the data i need in the DB and the other half comes from textbox1.textI take the text in textbox1 and pass it along with a value from the DB (Orig) to a function that returns miles.
[Code]....
Whit the above method everything displays correctly but i cannot sort on that column .I also tried using the miles() function in my select statement for my datasource but that was a nightmare and couldn't get that to work i either got "undeclared function "miles()" or when i fixed that i got "orig" not declared.Sorry code is so jumbled , entire code is below:
although i had to take the table that has my calculated column and make a view (so i could filter) and then bind the gridview to the view.
My question is as this.
1.) in order to get my calculated field i had to load my data into a table (as suggested)
2.)Add a column to the table and perform calculations
3.)make a dataview from the tables because i could not get the Gridview.datasource= ds.tables("loads").select("Deadhead <= " & sngRadius
4.)the largest of the 3 tables my query is based on contains about 7000 records. The way i have the logic & programming now everytime a new "truck location" is put in the textbox1 and "find loads/button1" is clicked. It calculates the deadhead miles of all 7000 records before filtering. I am filtering based on the deadhead miles.
Does anyone have any recomendation about how to speed this up a bit.
Also in order to get paging to work i had to rebind/filter the data again ... means looping through all 7000 records each time paging is called. This seems terribly ineffecient as i am already forced to use access instead of SQL.
Would i see a performance increase if i installed SQL or mySQL and create linked tables to the ones i use in access. or would access still be the bottleneck?
I don't know if the performance increase would be negligible as i still ultimately be getting the data from Access.
I have posted the entire code for the page below. When i originally started i didn't think there would be to much code so i left it all on one page instead of using code-behind. Would i gain anything by swapping to code-behind now?
I'm using a gridview to extract a set of records. I need to add another field to the gridview, which can calculate the difference between a date associated with each record and the current date.
I have a GridView, and I want Column1 to be equal to datatable data (filled by a SqlDataAdapter). Then I have two other fields by the SqlDataAdapter (first name, last name), and I want to have those two fields combined to form Column2. I have a TemplateField for my GridView that combines the first name and last name with Eval()'s, but the GridView places this combined field TemplateField and puts it as the first column.
How can I do this so that TemplateField can go in between fields that are databound?
I've got a Varchar2 field in my table which I want to convert to a CLOB. I am unsure whether the data would get truncated when selected. If so, what is the limit and does it depend on the database settings?
In my TOAD or SQLPLUS window it gets truncated but this may just be the environment settings. I'm not sure whether it would get truncated in my actual application (I can test this, but up to what size should I test?)
If it does get truncated, what's the best way to display the whole CLOB? There are other fields in my SELECT query, so I think I can't just loop through multiple rows. Is there any way out?
I hv a gridview in my page, and is getting populated on page load in code behind page ..now i want that, when the page gets load the first row should be selected and the all the values of the row should be get visible in the textboxes above the gridview
i sm hw got the default first row selected but the values of that row is not gettign diplayed in the textboxes.
I'm having a problem displaying all data from a couple of database tables in a GridView. Only one row is displayed. I have my SQL query posted in the "SQL Server etc..." forum, and I'm posting the code here in case there's something wrong with how I display the data in the GridView. The GridView should display 2 rows, but displays only 1.
i would like to find out how to go about displaying data from multiple database tables on the same page. What i mean is it would look like the feeds on the facebook home page where you can see the information like newply uploaded photo or a new post.
I have two tables, and i want to display any newly created row on my home page from either table in the same control. Currently, i have two gridviews, but i want the data from both tables be displayed together.
Let me try to explain my situation. I have a database table which contains, among other things, a boolean column called PermissionSlipRequired. I have a repeater on my page, and before each row in the database is shown in the repeater, I want to use my code behind to check the value of PermissionSlipRequired. Based on whether the value of PermissionSlipRequired is true or false, I want to change the text of a literal within the repeater. That's a real mouthful; hopefully some markup and code will clarify. Here's my repeater:
[Code]....
Here is what I've been able to come up with for my code behind. Needless to say, this code doesn't work.
[Code]....
As a former PHP user who is trying to migrate to asp.net.
I have a table "deposit_options.The form deposit_options.aspx, save the data.When you reopen deposit_options.aspx, I wish that the data are stored and displayed, and only update them.
