Hızlı yanıt: kod örneği
stackoverflow.com how-to-call-a-onclick-function-in-a-tag
Try onclick function separately it can give you access to execute your function which can be used to open up a new window, for this purpose you first need to create a javascript function there you can define it and in your anchor tag you just need to call your function.Example:See how to call it from your anchor tagUpdateVisit this jsbinhttp://jsbin.com/icUTUjI/1/editMay be this will help you a lot to understand your problem.
function newwin() { myWindow=window.open('lead_data.php?leadid=1','myWin','width=400,height=650')}
<a onclick='newwin()'>Anchor</a>