functionshuffleArray ( len ) { var arr = [], temp, index, i ; if ( !len ) { returnfalse; } for ( i = 1; i <= len; i++) { arr.push(i-1); }
//利用洗牌算法打乱数组 for ( i = 1; i <= len; i++ ) { //随机生成i到len之间的随机数 index = parseInt(Math.random() * ( len - i ), 10) + i; if ( index != i ) { temp = arr[i]; arr[i] = arr[index]; arr[index] = temp; } }