Event.observe(window,'load',getCheck);

function getCheck(){
	Event.observe(
		'input_btn',
		'click',
		function(){
			if(document.getElementById("url").value != "" &&
					(document.getElementById("url").value).indexOf("http://",0) != 0){
				document.getElementById("url").value = "http://"+document.getElementById("url").value;

			}
			if(document.getElementById("url").value == ""){
				alert('URLを入力して下さい');
			}else if(!document.getElementById("url").value.match(/^http:\/\/[-a-zA-Z0-9]+\.[-_.!~*\'()a-zA-Z0-9;\/?:\@&=+\$,%# \s]+$/)){
				document.getElementById("url").value = "";
				alert('不正なURLです');
			}
			else{
				var frm = document.getElementById("inputSearch");
				frm.action = "result.php";
				frm.method = "POST";
				frm.target = "_self";
				frm.submit();
			}
		}
	);
}