Question

    for (NSDictionary *firstDictionaryTemp in alertArray) {
        if ([firstDictionaryTemp objectForKey:@"user_name"]) {
            uId  = [firstDictionaryTemp objectForKey:@"u_id"]; 
            catId  = [firstDictionaryTemp objectForKey:@"cat_id"];
            myDictionary = [firstDictionaryTemp objectForKey:@"topic_detail"];
            for (NSDictionary *secDictionaryTemp in myDictionary) {                      
                if ([secDictionaryTemp  objectForKey:@"description"]) {
                   dictionaryDescription = [secDictionaryTemp objectForKey:@"description"];               
                   [result1 addObject : dictionaryDescription];           
                }
            }
        }

...

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section{

    return result1.count;
    // return [result1 count];
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"cell" forIndexPath : indexPath];
    UILabel *name2 = (UILabel *)[cell viewWithTag:30];
    name2.text = [result1 objectAtIndex : indexPath.row];
    return cell;
}

{

JSON ＆＃34;主题＆＃34;：[ { ＆＃34; topic_id＆＃34;：＆＃34; 66＆＃34;，＆＃34; cat_id＆＃34;：＆＃34; 74＆＃34;，＆＃34; topic_title＆＃34;：＆＃34; ssss＆＃34;，＆＃34; userid＆＃34;：＆＃34; 70＆＃34;，＆＃34; total_views＆＃34;：＆＃34; 1＆＃34;，＆＃34; user_name＆＃34;：＆＃34; abc＆＃34;，＆＃34; topic_detail＆＃34;：[ { ＆＃34;描述＆＃34;：＆＃34; Re＆＃34;，＆＃34; total_reply＆＃34;：0 } ] ＆＃34; is_bookmark＆＃34;：＆＃34; false＆＃34; }， { ＆＃34; topic_id＆＃34;：＆＃34; 43＆＃34;，＆＃34; cat_id＆＃34;：＆＃34; 74＆＃34;，＆＃34; topic_title＆＃34;：＆＃34; ee＆＃34;，＆＃34; userid＆＃34;：＆＃34; 70＆＃34;，＆＃34; total_views＆＃34;：＆＃34; 1＆＃34;，＆＃34; user_name＆＃34;：＆＃34; abc＆＃34;，＆＃34; topic_detail＆＃34;：[ { ＆＃34;描述＆＃34;：＆＃34; Ee＆＃34;，＆＃34; total_reply＆＃34;：0 } ] ＆＃34; is_bookmark＆＃34;：＆＃34; false＆＃34; }， { ＆＃34; topic_id＆＃34;：＆＃34; 40＆＃34;，＆＃34; cat_id＆＃34;：＆＃34; 74＆＃34;，＆＃34; topic_title＆＃34;：＆＃34; demo2＆＃34;，＆＃34; userid＆＃34;：＆＃34; 66＆＃34;，＆＃34; total_views＆＃34;：＆＃34; 1＆＃34;，＆＃34; user_name＆＃34;：＆＃34; 1＆＃34;，＆＃34; topic_detail＆＃34;：[ { ＆＃34;说明＆＃34;：＆＃34; demo2＆＃34;，＆＃34; total_reply＆＃34;：0 } ] ＆＃34; is_bookmark＆＃34;：＆＃34; false＆＃34; }， { ＆＃34; topic_id＆＃34;：＆＃34; 39＆＃34;，＆＃34; cat_id＆＃34;：＆＃34; 74＆＃34;，＆＃34; topic_title＆＃34;：＆＃34; demo＆＃34;，＆＃34; userid＆＃34;：＆＃34; 66＆＃34;，＆＃34; total_views＆＃34;：＆＃34; 1＆＃34;，＆＃34; user_name＆＃34;：＆＃34; 1＆＃34;，＆＃34; topic_detail＆＃34;：[ { ＆＃34;说明＆＃34;：＆＃34;演示＆＃34;，＆＃34; total_reply＆＃34;：0 } ] ＆＃34; is_bookmark＆＃34;：＆＃34; false＆＃34; } ] }

Answer 1

if alertArray.count > 0
{
     // execute your code
}
else
{
    // empty array
}

检查数组是否为空是很简单的。希望这会对你有所帮助。

Answer 2

如果你正在进入其他部分。那么你在做什么呢？分享代码

if alertArray.count > 0
{
     // execute your code
}
else
{
    // empty array
}

如果NSMutableArray * Result1中没有数据，应用程序崩溃。 [__NSCFConstantString countByEnumeratingWithState：objects：count：]：

2 个答案: