Develop Reference

How do I make the foreign key field in radgridview or datagridview a dropdownlist the user can choose from?

the form in question
I want to make the CompanyRegion_ID a dropdown list of values a user can select from, as I cannot add a foreign key directly from the gridview in any other way.

RadGridView from the Telerik UI for WinForms suite offers а GridViewComboBoxColumn which displays a set of predefined text values in a drop-down list. Please refer to the following help article demonstrating how to set up such a column in the grid: https://docs.telerik.com/devtools/winforms/controls/gridview/columns/column-types/gridviewcomboboxcolumn

Contains filter search doesn't work for devexpress gridview c#

I have a grid view column called LineNumber i set the autofiltercondition to contains .as you can see here :
But it doesn't work in running as you can see .and i have to enter the whole linenumber to find it .
Should i set something else property ?as you can see i have to enter 1.1/2... to find the line,but i need something like this %my text% in sqlserver

Please go through documentation of AutoFilterCondition Enumeration
Enumerates the comparison operator types for the filter conditions
created for specific columns via the automatic filtering row.
This will work if you have either enabled AutoFilter Row functionality or filter criteria in code.
For the FilterPopupMode Enumeration -
Contains values that specify the filter dropdown style for grid columns.
You have set it to CheckedList, So the filter dropdown is represented as a checked list of filter items. In this mode, an end-user can select more than one item simultaneously. When the dropdown window is closed by clicking the OK button, the View will display those records that contain the checked values
Hope this information help you..
References:
Autofilter Contains
AutoFilter Row problem with LIKE conditions

Insert new row in gridview by specific value

I'm using Devexpress tool anyone please help me?
I'm using Devexpress tool to develop my website. But i have some problems so i hope anyone could help me. I really need it in my project. Please see here:
http://www.fiditour.com/dattourtructuyen.aspx?id=731
look section above capcha. I have 2 questions:
- How they can add textbox in gridview?
- How they can add new row by value in textbox?
Thank for reading!

That is not textboxes in the grid. They are editable cells.
You can access the values entered by using the handler of the first row, then like #Давид Дача Милинкови mentionned, you add the specified row.

So as to have a textbox inside the column you must insert a GridViewDataTextColumn not just a GridViewDataColumn.
In the CellEditorInitialize event of the Grid you can pass the Default Value to e.Editor.

Update a data row inside an asp.net Data Grid View

I think it would be easier for you to understand my problem if I explain the scenario a bit.
What I am doing is developing a system to a doctor using asp.net c#. For the creation of the prescription, I add a check box list for the list of medicines and submit button below it. When the submit button clicked selected check box list items added to the sql server database and show a data grid with the selected medicines in the same page.
In the data grid there are two columns for medicine name and dosage.Medicine name is taken from the database.I need to give the user the ability to enter the dosage through that grid view. I need to use update command because the record is already there in the sql server.But empty value in the dosage column.I tried to use update command in the data source control. But I can't figure out how to give the WHERE clause because I can't specify the database row which the updating record relate to.
I would be glad to hear some help from you. All the comments are welcome.

You need to set a parameter(s), please check this example to understand how it works. I guess, that you've added in the database some column that is unique identifier.. some autoincrement int or guid.

How to bind a existing column of DataGridView with datetimepicker control

I have gone through many articles but everyone redirects to
How to: Host Controls in Windows Forms DataGridView Cells.
But the problem lies here is that I dont want to add new column to my DataGridView which the article says to do it.I am having a DataGridView which is filled through the DataSource property of Grid.The data is coming from the database and filling the Dataset which indirectly fills the DataGridView.
So would like to ask how to add datetimepicker to my existing column of datagrid using the above article.So far I have created three classes namely CalendarColumn.cs, CalendarCells.cs and CalendarEditingControl.cs.
Also would like to ask about the NULL values the column has.Will the Null values will be handled by the classes or do we have to add some code?
The Output m getting is something like this---
and I want that extra column(Unnamed) not to appear in the Grid and show only the DateOfBirth column with DTP control as shown below--
Any links or articles would be appreciated.
Thanks in advance.

Take a look at this article, I hope it will be useful: DataGridViewExtension.