How can I invoke a server-side event from jQuery (Sharepoint 2010)?

问题

In my Sharepoint 2010 app, I'm handling most events client-side with jQuery. However, for the saving of data to the Sharepoint list, and the generation of a PDF file with that data, I want to handle that server-side, with C#.

I tried to invoke a C# event this way:

0) Aded an HTML button in my project's *.ascx file:

<button type="button" name="saveData" id="saveData">Save Data</button>

1) Added jQuery to respond to that button being clicked (in the same *.ascx file):

$("#saveData").click(function () {
      $('#hiddenSave').trigger('valuechanged');
  });

2) Created a hidden element in the server-side C# (in the *.ascx.cs file):

HiddenField hiddenSave = null;

protected void Page_Load(object sender, EventArgs e)
{
    base.OnPreRender(e);

    hiddenSave = new HiddenField();
    hiddenSave.ID = "hiddenSave";
    hiddenSave.ValueChanged += new EventHandler(hiddenSave_ValueChanged);
    this.Controls.Add(hiddenSave);
}

protected void hiddenSave_ValueChanged(object sender, EventArgs e)
{
    GeneratePDF();
}

private void GeneratePDF()
{
    ;//bla
}

But I never reach the "ValueChanged" event handler; $("#saveData").click() fires, but not hiddenSave_ValueChanged().

So do I need a tweak to this, or a completely different approach? How can I do as much as possible client-side with jQuery, but also run server-side/C# code where necessary, in a Sharepoint 2010 app?

UPDATE

A little more detail, and about additional things I've tried: I'm creating a button on a Sharepoint page dynamically (in C#) in my *.ascx.cs file:

Button btnSave = null;

protected void Page_Load(object sender, EventArgs e)
{
    base.OnPreRender(e);    

    this.Controls.Add(new LiteralControl("<br />"));
    btnSave = new Button();
    btnSave.ID = "btnSave";
    btnSave.Text = "Save the Data"; 
    btnSave.Click += new EventHandler(btnSave_Click);
    btnSave.Visible = false;
    this.Controls.Add(btnSave);
}

protected void btnSave_Click(object sender, EventArgs e)
{
    btnSave.Text = "You clicked me!"; 
    PostTravelData ptd = new PostTravelData();
}

I set it visible at the right time in the client-side jQuery in the *.ascx file:

$('#btnSave').show();

However, clicking the button does not reach the btnSave_Click() event - the breakpoint there is never reached, nor is the button's text changed. Why not?

Even when I don't set the button invisible (comment out the "btnSave.Visible = false;" line), the click handler isn't reached...is Page_Load() too late? Is there an earlier page event I can use that would work?

I tried moving it from Page_Load() to OnPreRender(), too, like this:

protected void OnPreRender(EventArgs e)
{
    this.Controls.Add(new LiteralControl("<br />"));
    btnSave = new Button();
    btnSave.ID = "btnSave";
    btnSave.Text = "Save the Data";
    btnSave.Click += new EventHandler(btnSave_Click);
    //btnSave.Visible = false;
    this.Controls.Add(btnSave);
}

...(and OnRender()) but the button doesn't even display...

And, trying a different tack, I commented out the dynamic creation server-side code and tried to attach to a button created in the HTML (*.ascx file):

<button type="button" name="saveData" id="saveData" runat="server" onclick="saveData_Click">Save Data</button>

(by adding the "runat server" and the onclick handler), and then adding this "code-behind" (*.ascx.cs)):

protected void saveData_Click(object sender, EventArgs e)
{
    PostTravelData ptd = new PostTravelData();
    SaveToList(ptd);
    GeneratePDF(ptd);
}

...but there was still no joy in Mudville -- the breakpoint in the handler is not reached.

Yet another attempt was:

In the *.ascx:

<asp:Button runat="server" id="saveData" name="saveData" onclick="saveData_Click" Text="Bla" />

In the code-behind:

saveData.Click += saveData_Click;

The "Bla" button is created, but clicking on it reaches not the breakpoint in the "saveData_Click" handler.

I even adapted some code from here like so:

Button btnSave = null;

. . .

protected override void CreateChildControls()
{
    btnSave = new Button();
    btnSave.Width = new Unit(150, UnitType.Pixel);
    btnSave.Text = "Can you see me?";
    btnSave.Click += new EventHandler(btnSave_Click);
    Controls.Add(btnSave);
}

...but I still do not reach the "protected void btnSave_Click(object sender, EventArgs e)" handler when I click the button.

Surely there's a way to get a handle on the button server-side and manipulate it (specifically, respond to its click event)...?!?

回答1:

First of all, as far as I know, there is no such event for input type hidden in a ascx page. If you create the input type hidden with runat server in the ascx code then you'll see that when you try to add this event it's not available. However there are other events like OnClick that you can simulate to get the desired result.

来源：https://stackoverflow.com/questions/32594884/how-can-i-invoke-a-server-side-event-from-jquery-sharepoint-2010

标签

jquery

html

sharepoint-2010