Change document.getElementById('personlist').getElementsByTagName('option')[11].selected = 'selected'. to document. ... <看更多>

Summary · The <select> element allows you to select one or multiple options. Add the multiple attribute to the <select> element to enable multiple selections. ... <看更多>

<label >Select: <select id="selectMode"> <option value="1">option_01</option> <option value="2">option_02</option> ... <看更多>

Hi @ChrisGitIt, I'm able to determine whether an option is selected or not using this property: https://jsbin.com/xatavo/edit?html,js,output. ... <看更多>