Getting tooltip of ASP.NET Radio button in java script.

This post in regards to a question that I have answered on stack overflow. Getting Tool tip of the Radio button in JavaScript. Where user asks why he is not able to get tooltip with document.GetElementById and Client Id of ASP.NET Radio button control like following.

document.getElementById('<%= rbSelectedIds.ClientID %>').title

While answering this question, I have found that there are lots of people not aware about this. So I thought it is a good idea to write a blog post about it.

By default ASP.NET Radio button and check box controls rendered under span when you have attribute like tooltip. Because System.Web.UI.WebControls namespace may render differently in  different browsers and to achieve same functionality in all the browsers they are rendering with span.

There is a complete discussion there one in one of the StackOverFlow.com

Why does ASP.Net RadioButton and CheckBox render inside a Span?

Example : Getting ASP.NET Radio button tooltip in JavaScript:

So let’s take same example as mentioned in that question. Following is my HTML Code. Below is radio button HTML code.

<div>
       <ASP:RadioButton runat="server" ID="myRadioButton" 
            Text="Yes" ToolTip="Yes"/>
</div>

Now when you run this in browser it will render this radio button is render with surrounded by span like follow.



You can see that title attribute is given to span tag instead of radio button. Now let’s create a ASP.NET button to get tooltip of that radio button like below.

<asp:Button runat="server" Text="Get Tooltip" 
        OnClientClick="getToopTip();"/>

So we are done with button now it’s time to write a JavaScript. Following is a code for JavaScript.

function getToolTip() {
    var sParentElement = document.getElementById("<%=myRadioButton.ClientID%>").parentElement;
    var tooltip = sParentElement.title;
    alert(tooltip);
}

So we are done with code. Now it’s time to run this code in browser. And when you click on button it will show alert with tool tip of radio button.



That’s it. Hope you like it. Stay tuned for more.