More on JavaScript form Validation. Here is the code to read the data. Tip: This event is similar to the oninput event. ListBox Disable: using disabled property we can disable a listbox by radio button. How can I pass the complete combobox with its select id, and how can I pass other parameters on fire of the onChange event? The this. Example Example. - JavaScript - Get selected value from dropdown list. Using the select() method of the HTML DOM Input Text Object to select some content of a text field. Listboxes can be accessed through JavaScript in the same way that dropdown boxes are accessed. If the ListBox OnChange starts working, well, than you have to solve the problem with the JavaScript (that probably is deactivating the Outsystems handler), or not use it at all. When it postback, my listsearch extender does not work. If you have JavaScript that is messing with the ListBox, I would first remove it to see if it is the cause (most likely). The difference is that the oninput event occurs immediately after the value of an element has changed, while onchange occurs when the element loses focus. but when I choose an item in listbox, it cause a postback. Can you help? is passing the value.But how to pass other select box selected value in first select box function? I have to pass the two select box selected value in the functions which are called on onchange method. Adding option: Adding options to a listbox dynamically onchange event in JavaScript is an important event which is used for the event changes occurring at the time of performing the event. I want to show one combobox-A, which is an HTML