problem while getting values from dynamically created textboxes

 Hi Friends

I have created some text boxes dynamically and I have problem while accessing their changed values. And I am using the following code. 

1    TextBox t =(TextBox) this.form1.FindControl("field1");
2    string name = t.Text;

  When I try to execute the second line i.e. getting values from the text box, it results with Object reference not set to an instance of object.

 

field1, fiedl2.... all are valid text box ids and they are present in the page.

how to solve this?

0
abidshahzad
12/23/2008 6:12:32 AM
asp.net.web-forms 93655 articles. 5 followers. Follow

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If you are using master page then field1 is changed to other name. Generally for object reference not set type of errors these two ;ines will not be sufficient to guess actual error.

Also if you are trying this after post back then dyanamic controls no  longer exists on page

Thanks

Mohan Pathare

 

 

0
mohanpathare
12/23/2008 7:41:08 AM

 Thanks for reply

 the vlaues are from database and textboxes are generated according to the fields. And contain data from database.

I have to update and save the data. How this can be handled.

 

0
abidshahzad
12/23/2008 7:48:43 AM

Hi abidshahzad,

Try using this:

 

TextBox t = FindControl("field1") as TextBox;

 

The 'as' keyword performs faster than a cast. Also, you need to retrieve the control from the page, not the form.  This example assumes there is a <asp:TextBox ID='field1" runat="server" /> on your page.

Hope this helps.


Happy Coding,

SyntaxC4

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SyntaxC4
12/23/2008 7:56:31 AM
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