How to bind a textbox to an a data source

[Morris Neuman]

Hi,

I want to bind a textbox (not in a gridview or detailsview or formview),
just a regular textbox to a field in an AccessDataSource or SQLDataSource.

How can I do that?

 

[Tim Van Wassenhove]

Morris Neuman schreef:

Hi,

I want to bind a textbox (not in a gridview or detailsview or formview),
just a regular textbox to a field in an AccessDataSource or SQLDataSource.

Exactly what is an AccessDataSource?

Under the assumption that you have class (eg: class A and an instance a)
with a property (eg: B) you can bind to the Text property of a Textbox
(eg: c) as following:

c.DataBindings.Add("Text", a, "B");

If you create a datasource in the designer, you can also set this via
the properties window -> DataBindings -> Text

 

[Riki]

Hi,

I want to bind a textbox (not in a gridview or detailsview or
formview), just a regular textbox to a field in an AccessDataSource
or SQLDataSource.

How can I do that?

The easiest way is still to put that textbox in the ItemTemplate of a
FormView,
and binding the FormView to the datasource.

 

[Morris Neuman]

Thanks. Can the Textbox in the itemtemplate be bound to a datasource
differnt from the one bound to the FornView? I have done that with
Dropdownlist control in a itemtemplate of a formview or gridview but can't
seem to do that with a textbox control.

Any suggestions?

 

[Riki]

Thanks. Can the Textbox in the itemtemplate be bound to a datasource
differnt from the one bound to the FornView? I have done that with
Dropdownlist control in a itemtemplate of a formview or gridview but
can't seem to do that with a textbox control.

That's because a dropdownlist is a list control.

Why do you want the textbox to have its own datasourcecontrol?

Just bind it inside the itemtemplate to the data of the formview, and you're
done.

 

[Steven Cheng[MSFT]]

Hi Morris,

For TextBox control, it is a simple databound webcontrol, you can simply
bind its property with an object/value or function e.g.

<asp:TextBox .... Text=<%# function or object %> />

For DataSource control, it is designed to support template based databound
control or list databound control rather, so those simple controls like
Label , Textbox doesn't directly support binding with it.

Would you provide some further information about the scenario in your page?
So far according to your description, I think it may be better that we use
code to programmatically retrieve value and assign it to textbox(if it is
already in a template control which bound to another datasource).

Sincerely,

Steven Cheng

Microsoft MSDN Online Support Lead


This posting is provided "AS IS" with no warranties, and confers no rights.

 

[Morris Neuman]

OK. I have 2 different scenario.

Scenario 1.
I have a formview that I use to insert records. It adds the records to
mailbox table (Access or SQL). So I have the formview bound to either
AccessDataSource or SQLDataSource controls.

I also have a table (mailboxdefault) that has default values for some of the
mailbox fields. These can be changed by the system administrator.

What I am trying to do is the following:
When the formview control is displayed in insert mode, I want the fields to
display the values from the mailboxdefault, allowing the user to change them
if desired or leave the defaults as is, and then add the record to the
mailbox table.

Can I bind the textbox control in the inserttemplate to a different data
source than the one use to bind the formview?


Scenario 2.
Can I bind a regular textbox control (not in a formview or gridview, etc) to
a datasource so I can display a value from a table?

Thanks to everyone for your help.

 

[Riki]

OK. I have 2 different scenario.

Scenario 1.
I have a formview that I use to insert records. It adds the records
to mailbox table (Access or SQL). So I have the formview bound to
either AccessDataSource or SQLDataSource controls.

I also have a table (mailboxdefault) that has default values for some
of the mailbox fields. These can be changed by the system
administrator.

What I am trying to do is the following:
When the formview control is displayed in insert mode, I want the
fields to display the values from the mailboxdefault, allowing the
user to change them if desired or leave the defaults as is, and then
add the record to the mailbox table.

Can I bind the textbox control in the inserttemplate to a different
data source than the one use to bind the formview?

Since you're using the formview only for inserting, you can configure
the datasourcecontrol as follows:
1) create the datasource with the wizard in Visual Studio. Use the mailbox
table. This will create the right InsertCommand value for what you want, but
the SelectCommand will still point to the mailbox table, which is not what
you want.
2) modify the SelectCommand in order to select the default values from the
mailboxdefault table.

This will produce what you want.

Scenario 2.
Can I bind a regular textbox control (not in a formview or gridview,
etc) to a datasource so I can display a value from a table?

Yes, but not to a datasourcecontrol (as far as I know).
You can write some code to databind your textbox when the page loads.

 

[Steven Cheng[MSFT]]

Thanks for your reply Morris and thanks for Riki's further suggestion.

For scenario1, I agree with Riki that if the FormView is used for inserting
item only, you can consider manually change the "SelectStatement" of the
datasource control so as to let it return values from the "DefaultMailBox"
table. However, if your FormView will be used to both insert and
update/display items, I'm afraid you have to manually use code to
programmatically retrieve the default values from database and bind it to
the textboxes in Inserttemplate(in PreRender event or any other place that
can access the loaded controls in InsertTemplate).

For scenario2, since TextBox can not directly bind to datasource control, I
suggest you consider define some codebehind helper functions that retrieve
the proper value(from database or ...) and use those helper function in
your databinding expression. e.g.

<asp:TextBox ..... Text="<%# GetValueFromHelper() %>" />....

Sincerely,

Steven Cheng

Microsoft MSDN Online Support Lead


This posting is provided "AS IS" with no warranties, and confers no rights.

 

[Morris Neuman]

Thanks to everyone for all the help. I tried as suggested by Riki and
retrieved the default fields in the select statement used to bind the
formview.

Then I changed the field in the formview that I want to display the default
value, to a template field. I bound the item template to the default value
but the value does not show on the screen. I also bound the insert template
to the default value but that did not work either.

Question: If I want to display on the screen the mailboxdefault value but
insert to the mailbox record, which template should I use for the display and
which template should I use for the insert? I am only displaying the formview
in insert mode when the user clicks on the add mailbox link button.

 

[Fred]

The problem is that, in VS2003 using web forms, the text control had a
property - "Databinding" that simplified connecting the control to a
datasource. It could be done visually during design and was very simple
to modify.

In VS2005, I want to do the same thing: I want to add a textbox to a
form and then bind it to a datasource, and I want to do it visually,
without having to go to the HTML source and add something like,
Text='<%# DataBinder.Eval(HelpDeskDV, "[0].ContactName", "{0}") %>'.

So the question is: how do I assign a datasource to an existing textbox
on a web form?

Regards,
Fred

 

[Morris Neuman]

Hi,

Any ideas or thoughts on my 5/1 posting?

Any help is most appreciated.

 

[Steven Cheng[MSFT]]

Hi Morris,

I've investigated the FormView databinding model further and find that
using the built-in "SelectCommand" does not help for this scenario. Since
FormView will need to use two way databinding, the InsertCommand need to be
set to the actual database table(you want to insert record). For the
default table's values, I'm afraid you need to maually assign them to the
TextBoxes in the "Inserttemplate". e.g.

=================
protected void FormView1_PreRender(object sender, EventArgs e)
{
if (FormView1.CurrentMode == FormViewMode.Insert)
{
TextBox txt1 = FormView1.FindControl("nameTextBox") as TextBox;
TextBox txt2 = FormView1.FindControl("descriptionTextBox") as
TextBox;

//replace default value with the one you retrieve from database
txt1.Text = "default name..";
txt2.Text = "default description..";

}
}
====================

Sincerely,

Steven Cheng

Microsoft MSDN Online Support Lead


This posting is provided "AS IS" with no warranties, and confers no rights.

 

[Morris Neuman]

Hi Steven,

Thanks for your response and your help.

The default value from is a field from a datasource control defined as a
variable in my web.config AppSettings as MyDataSource. This control can
point to either an AccessDataSource or SqlDataSource based on web.config.

I also have the default value as a boundfield in my gridview control,
however I have iit set to invisible.

So the question is - in your comment you have
txt1.Text = "default name..";
but in that case "default name is a literal. How do I set txt1.Text set to
the value in either the database source or the boundfield in the gridview.

Thanks again for your help.

 

[Steven Cheng[MSFT]]

Thanks for your reply Morris,

If you need to get the data field value from DataSource control, you can
also do it programmatically. ASP.NET 2.0 DataSource control provide method
to let you explicitly perform the query and get the resultset. e.g.


=========================
protected void FormView1_PreRender(object sender, EventArgs e)
{
if (FormView1.CurrentMode == FormViewMode.Insert)
{
TextBox txt1 = FormView1.FindControl("nameTextBox") as TextBox;
TextBox txt2 = FormView1.FindControl("descriptionTextBox") as
TextBox;

IEnumerable result =
SqlDataSource2.Select(DataSourceSelectArguments.Empty);
DataView dv = result as DataView;

string defaultname = (string)dv[0]["name"];
string defaultdesc = (string)dv[0]["description"];

txt1.Text = defaultname;
txt2.Text = defaultdesc;


//............

}
}
===============================

Sincerely,

Steven Cheng

Microsoft MSDN Online Support Lead


This posting is provided "AS IS" with no warranties, and confers no rights.

 

[Morris Neuman]

Hi Steven,

Tried the code per your suggestion, however I get the following error:
The type or namespace name 'DataView' could not be found (are you missing a
using directive or an assembly reference?
What do I need to change?

Also in your post you specify SqlDataSource1. I use either SqlDataSource1
or AccessDataSource1 based on a variable MyDataSource from the AppSetting
section of the web.config.
How would I modify your statement to base selection on the MyDataSource app
setting?

Thanks as always for your help.

 

[Steven Cheng[MSFT]]

Hi Morris,

As for the DataView class, it is under the System.Data namespace, have you
imported the namespace in your code behind file?

For SqlDataSouce and AccessDataSource, they've both implemented the
"Select" method that can directly perform query in manual code and return
the queried resultset. Make sure you set "DataSourceMode" of them to
"DataSet"(the default value) so that the returned object from Selecct
method would be a DataView object. For detecting whether it is
SqlDataSource or AccessDataSource, I suggest you typeof() directive (in C#)
to detect the type (use if...else block) to separate your code logic of the
datasource control's converting. How do you think?

Sincerely,

Steven Cheng

Microsoft MSDN Online Support Lead


This posting is provided "AS IS" with no warranties, and confers no rights.