为什么图片显示不出来呢？

Question

var bannerImage=new Array(); bannerImage[0]="'/index2/img/cool (1).png'"; bannerImage[1]="'/index2/img/cool (2).jpg'"; bannerImage[2]="'/index2/img/cool (2).png'"; bannerImage[3]="'/index2/img/cool (3).png'"; bannerImage[4]="'/index2/img/cool (3).jpg'"; bannerImage[5]="'/index2/img/cool (4).png'"; bannerImage[6]="'/index2/img/cool (4).jpg'"; var randomImageIndex=Math.round(Math.random()*6); document.write("<img src=bannerImage[randomImageIndex]/>")