警告：控制到达无效功能的结束 - iPhone [英] Warning: control reaches end of non-void function - iPhone

问题描述

我通过以下代码继续'警告：控制到达非空函数的结尾'：

I keep getting 'warning: control reaches end of non-void function' with this code:

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

 if (section ==0)

 {
  return [comparativeList count];
 }

 if (section==1) 
 {
  return [generalList count];
 }

 if (section==2)
 {

  return [contactList count];

如何摆脱此警告？

谢谢。

推荐答案

在此处添加返回0; 方法结束。如果没有满足 if 条件，它基本上是故障安全的。

Add a return 0; at the end of your method. It's basically a failsafe, if none of the if conditions are met.

如果你想确保满足其中一个条件， return -1; 应该导致应用程序抛出异常并崩溃，这可能会帮助您追踪错误。

If you want to make sure one of the conditions is met, return -1; should cause the application to throw an exception and crash, which might help you track down errors.

您可能还会考虑修改此方法并替换 if 带有 switch-case 树的语句。使用 switch-case 树，您可以非常轻松地添加新部分并在 UITableView 中重新排列其顺序。通过使用合理的命名约定，代码变得非常容易阅读。

You might also look at modifying this method and replacing the if statements with a switch-case tree. With a switch-case tree, you can very easily add new sections and rearrange their order in a UITableView. The code becomes trivially easy to read by using sensible naming conventions.

这很容易; Fraser Speirs有一个关于如何设置的良好解释。

It's really easy; Fraser Speirs has a good explanation on how to set this up.

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