Postback Issues inside GridView TemplateField

The following code is causing me a postback when i select a value from the ajax combobox and as such the row position changes sometimes by 4-5 rows and sometimes even more. I have been working on it for the last 3 days but found no satisfactory solution. I also used scrollIntoView. But that too works sometimes only. Here is the code: ' CssClass="form-control" Visible='<%# IsInEditMode %>' onmouseover="show(this)" onmouseout="hide(this)" > ' CaseSensitive ="false" ItemInsertLocation="OrdinalValue" CssClass="form-group " Width="100%" onselectedindexchanged="cmbresultnew_SelectedIndexChanged" EnableViewState="true">

It looks like you're dealing with a postback issue caused by the onselectedindexchanged event of an AJAX ComboBox in a Web Forms application. To avoid the page jumping around and to maintain the row position after the postback, consider the following strategies:

Maintain Scroll Position on Postback: Ensure that the scroll position is maintained after postback. ASP.NET provides a built-in mechanism for this.

2. Client-Side Handling: Use JavaScript to save the scroll position before the postback and restore it afterward.

In your ASPX page, include a hidden field to store the scroll position:

3. UpdatePanel: Wrap the ComboBox inside an UpdatePanel to enable partial page updates and avoid full page postbacks.

Prevent Full Postback: Handle the onselectedindexchanged event using AJAX to prevent a full postback. You can use PageMethods or an UpdatePanel for this purpose.

Example using PageMethods:

In your code-behind, create a static method to handle the selection change:

[WebMethod]
public static void cmbresultnew_SelectedIndexChanged(string selectedValue)
{
    // Your logic here
}

And in your JavaScript, call this method using PageMethods:

function cmbresultnew_SelectedIndexChanged(sender, args) {
    PageMethods.cmbresultnew_SelectedIndexChanged(args.get_value(), onSuccess, onError);
}

function onSuccess(result) {
    // Success logic here
}

function onError(error) {
    // Error handling here
}

By using these strategies, you can minimize or eliminate the postback issues and maintain the scroll position of your page.

1 Reply

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Prasad Raveendran2y ago
It looks like you're dealing with a postback issue caused by the onselectedindexchanged event of an AJAX ComboBox in a Web Forms application. To avoid the page jumping around and to maintain the row position after the postback, consider the following strategies:
1. Maintain Scroll Position on Postback: Ensure that the scroll position is maintained after postback. ASP.NET provides a built-in mechanism for this.
2. Client-Side Handling: Use JavaScript to save the scroll position before the postback and restore it afterward.
In your ASPX page, include a hidden field to store the scroll position:
3. UpdatePanel: Wrap the ComboBox inside an UpdatePanel to enable partial page updates and avoid full page postbacks.
```
    
        
        
    
```
Prevent Full Postback: Handle the onselectedindexchanged event using AJAX to prevent a full postback. You can use PageMethods or an UpdatePanel for this purpose.

Example using PageMethods:
In your code-behind, create a static method to handle the selection change:
```
[WebMethod]
public static void cmbresultnew_SelectedIndexChanged(string selectedValue)
{
    // Your logic here
}
```
And in your JavaScript, call this method using PageMethods:
```
function cmbresultnew_SelectedIndexChanged(sender, args) {
    PageMethods.cmbresultnew_SelectedIndexChanged(args.get_value(), onSuccess, onError);
}

function onSuccess(result) {
    // Success logic here
}

function onError(error) {
    // Error handling here
}
```
By using these strategies, you can minimize or eliminate the postback issues and maintain the scroll position of your page.