数组排序

 NSMutableArray *copyArray =[NSMutableArray arrayWithArray:tempArray];
    [copyArray sortUsingComparator:^NSComparisonResult(id obj1, id obj2) {

        ChannelAnalyseInfo *info1 = (ChannelAnalyseInfo *)obj1;

        ChannelAnalyseInfo *info2 = (ChannelAnalyseInfo *)obj2;


       NSInteger m1 =  info1.totalQuantity;
        NSInteger m2 = info2.totalQuantity;


        /**
         *  必须换成整型，字符串对比会不准

         */

        if (m1<m2) {

            return NSOrderedAscending;

        }else if(m1>m2){

            return NSOrderedDescending;

        }else{

            return NSOrderedSame;


        }
    }];