我有三個按鈕命名(標題)你好,沒有,天堂和一個標籤(IBOutlet UIlabel實驗室)。我想爲三個差異按鈕點擊顯示三個差異消息。但是下面的代碼沒有完成這個。任何人都可以提出任何想法objective c NSString比較
-(IBAction)buttonclick:(id)sender
{
NSString *title=[sender titleForState:UIControlStateNormal];
if([title isEqualToString:@"hello"])
{
NSString *str=[[NSString alloc] initWithFormat:@"abc"];
}
else if([title isEqualToString:@"nothing"]) {
NSString *str=[[NSString alloc] initWithFormat:@"def"];
}
else if([title isEqualToString:@"heaven"])
{
NSString *str=[[NSString alloc] initWithFormat:@"ijk"];
}
lab.text=str;
[str release];
}
輸出:
warning:unused variable str;