我找到了一个简单的解决方法(我认为):

var marker = new google.maps.Marker();

function Clear(){
     marker.setMap(null);
}

简单地做以下几点:

I.声明一个全局变量:

var markersArray = [];

2定义一个函数:

function clearOverlays() {
  for (var i = 0; i < markersArray.length; i++ ) {
    markersArray[i].setMap(null);
  }
  markersArray.length = 0;
}

OR

google.maps.Map.prototype.clearOverlays = function() {
  for (var i = 0; i < markersArray.length; i++ ) {
    markersArray[i].setMap(null);
  }
  markersArray.length = 0;
}

3在调用以下函数之前，在'markerArray'中插入标记:

markersArray.push(marker);
google.maps.event.addListener(marker,"click",function(){});

IV.调用clearoverlay ();或map.clearOverlays ();在任何需要的地方发挥作用。

就是这样! !

在新版本v3上，他们建议保持在数组中。如下。

参见overlay-overview中的示例。

var map;
var markersArray = [];

function initialize() {
  var haightAshbury = new google.maps.LatLng(37.7699298, -122.4469157);
  var mapOptions = {
    zoom: 12,
    center: haightAshbury,
    mapTypeId: google.maps.MapTypeId.TERRAIN
  };
  map =  new google.maps.Map(document.getElementById("map_canvas"), mapOptions);

  google.maps.event.addListener(map, 'click', function(event) {
    addMarker(event.latLng);
  });
}

function addMarker(location) {
  marker = new google.maps.Marker({
    position: location,
    map: map
  });
  markersArray.push(marker);
}

// Removes the overlays from the map, but keeps them in the array
function clearOverlays() {
  if (markersArray) {
    for (i in markersArray) {
      markersArray[i].setMap(null);
    }
  }
}

// Shows any overlays currently in the array
function showOverlays() {
  if (markersArray) {
    for (i in markersArray) {
      markersArray[i].setMap(map);
    }
  }
}

// Deletes all markers in the array by removing references to them
function deleteOverlays() {
  if (markersArray) {
    for (i in markersArray) {
      markersArray[i].setMap(null);
    }
    markersArray.length = 0;
  }
}

我刚刚尝试了kmlLayer.setMap(null)，它工作。不确定这是否适用于普通的标记，但似乎工作正确。

要从地图中删除所有标记，创建如下函数:

1.addMarker(location):这个函数用于在地图上添加标记

2.clearMarkers():该函数从map中移除所有标记，而不是数组中

3.setMapOnAll(map):这个函数用于在数组中添加标记信息

4.deleteMarkers():该函数通过删除对数组中所有标记的引用来删除它们。

// Adds a marker to the map and push to the array.
      function addMarker(location) {
        var marker = new google.maps.Marker({
          position: location,
          map: map
        });
        markers.push(marker);
      }


// Sets the map on all markers in the array.
      function setMapOnAll(map) {
        for (var i = 0; i < markers.length; i++) {
          markers[i].setMap(map);
        }
      }



// Removes the markers from the map, but keeps them in the array.
  function clearMarkers() {
    setMapOnAll(null);
  }

// Deletes all markers in the array by removing references to them.
      function deleteMarkers() {
        clearMarkers();
        markers = [];
      }

在这里你可以找到一个如何删除标记的例子:

https://developers.google.com/maps/documentation/javascript/examples/marker-remove?hl=es

// Add a marker to the map and push to the array.
function addMarker(location) {
  var marker = new google.maps.Marker({
    position: location,
    map: map
  });
  markers.push(marker);
}

// Sets the map on all markers in the array.
function setAllMap(map) {
  for (var i = 0; i < markers.length; i++) {
    markers[i].setMap(map);
   }
}

// Removes the markers from the map, but keeps them in the array.
function clearMarkers() {
  setAllMap(null);
}

// Deletes all markers in the array by removing references to them.
function deleteMarkers() {
  clearMarkers();
  markers = [];
}