js两种拼接字符串的简单方法(必看)

function(msgArr) {  var len = msgArr.length;  var n = 0 ;  var htmlSpan = "";  for (var j = 0; j < len - 1; j++) {    htmlSpan += '<span>・</span>';  }  htmlSpan += '<span class="on">・</span>';  var imgs = [];  var img = [];  img[0] = '<a href="' + ctx + '/webservice/dish/detail?id=';  img[1] = '#';  img[2] = '"><img src="';  img[3] = '#';  img[4] = '"></a>';  for (var i = 0; i < len; i++) {    img[1] = msgArr[i].id;    img[3] = msgArr[i].pic;    imgs.push(img.join(""));  }  $("#banner_list").html(imgs.join(""));  $(".dots").html(htmlSpan);}