var _pattern=/^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}$/
function clearText(obj){
    var o = document.getElementById('Input');
    o.readOnly = false;
    if(_pattern.test(o.value) == false){
        o.value = "请在此输入ip地址";
        o.select();
    }
    obj.checked="checked";
    document.getElementById('schoolChoose').style.display = 'none';
    o.focus();
}

function testIp()
{
    if(document.getElementById('ip').checked != true)
        return true;
    var ipInput=document.getElementById("Input");
    var text=ipInput.value;
    var tmp= _pattern.test(text);
    if(tmp==false){
        alert("您输入的ip地址不正确，请重新输入");
        ipInput.value="";
        ipInput.focus();
        return tmp;
    }
}