设置级别

<html>
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <meta name="viewport" content="initial-scale=1.0, user-scalable=no" />
    <style type="text/css">
        body, html {width: 100%;height: 100%;margin:0;font-family:"微软雅黑";}
        #allmap{width:100%;height:500px;}
        p{margin-left:5px; font-size:14px;}
    </style>
    <script type="text/javascript" src="http://api.map.baidu.com/api?v=2.0&ak=sSelQoVi2L3KofLo1HOobonW"></script>
    <title>缩放地图</title>
</head>
<body>
    <div id="allmap"></div>
    <p>初始化展示中心点为(116.4035,39.915),缩放级别为8的北京市地图,2秒后,通过设置缩放级别将地图放大到14级</p>
</body>
</html>
<script type="text/javascript">
    // 百度地图API功能
    var map = new BMap.Map("allmap");  
    //map.centerAndZoom(new BMap.Point(116.4035,39.915),8); 
    map.centerAndZoom('宿迁',8); 
    setTimeout(function(){
        map.setZoom(14);    // setZoom 方法,负责设置级别,只有停留几秒,才能看到效果
    }, 2000);  //2秒后放大到14级
    map.enableScrollWheelZoom(true);
</script>

禁止拖拽

<!DOCTYPE html>
<html>
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <meta name="viewport" content="initial-scale=1.0, user-scalable=no" />
    <style type="text/css">
        body, html,#allmap {width: 100%;height: 100%;overflow: hidden;margin:0;font-family:"微软雅黑";}
    </style>
    <script type="text/javascript" src="http://api.map.baidu.com/api?v=2.0&ak=sSelQoVi2L3KofLo1HOobonW"></script>
    <title>拖拽地图</title>
</head>
<body>
    <div id="allmap"></div>
</body>
</html>
<script type="text/javascript">
    // 百度地图API功能
    var map = new BMap.Map("allmap");            // 创建Map实例
    map.centerAndZoom(new BMap.Point(116.4035,39.915),8);  //初始化时,即可设置中心点和地图缩放级别。
    map.enableScrollWheelZoom(true);
    map.disableDragging();     //禁止拖拽
    setTimeout(function(){
       map.enableDragging();   //两秒后开启拖拽
       //map.enableInertialDragging();   //两秒后开启惯性拖拽
    }, 2000);
</script>

根据实际情况来使用吧!