Asp.NET DropDownList SelectedItem.Value not changing

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Answer 1

hey for first index to add all not required to add. you need to insert on particular index number

MyList.Items.Insert(0, "ALL");

Answer 2

Yes you are missing to add drop down list Autopostback=true..

Please try with following in your .aspx page

Answer 3

Your code is probably executing after postback too, clearing the box, hence losing selection and all.

If so, try wrapping the code in something like if( !Page.IsPostBack ) { ... }.

Answer 4

If you're databinding in Page_Load, you're essentially also resetting the SelectedItem.

You should wrap whatever binding code that exists in Page_Load inside an if(!IsPostBack) block.

if(!Page.IsPostBack)
{

    // Your binding code here ...

}

Answer 5

So this answer is the "obvious" solution to the most common cause. However, there is one more surprising issue that can cause this! My list values came from a database and the values had linefeed and carriage return: "\r\n". These values look like an innocent space, but actually they are not! My solution was to remove these hidden Char values. Hope it helps.