预期'）'但无法找到应该去的地方

Xcode is telling me that I'm missing a ')' but I can't tell where it should go; it makes no sense to me. Have commented out the error message.

Xcode告诉我,我错过了')',但我不知道应该去哪里;对我来说完全是无稽之谈。已注释掉错误消息。

Can you look at the code and tell me where it's wrong?

你能看一下代码并告诉我哪里错了吗?

Thank you.

CalculatorViewController.m

#import "CalculatorViewController.h"

@interface CalculatorViewController()
@property (nonatomic) BOOL userIsInTheMiddleOfEnteringANumber;

@end

@implementation CalculatorViewController
@synthesize display;
@synthesize userIsInTheMiddleOfEnteringANumber;

- (IBAction)digitPressed:(UIButton *)sender 
{

    NSString *digit = [sender currentTitle];
    self.display.text = [self.display.text stringByAppendingString:digit];
    if (self userIsInTheMiddleOfEnteringANumber) {    // Expected ')'
        self.display.text = [self.display.text stringByAppendingString:digit];
    } else {
        self.display.text = digit;
        self.userIsInTheMiddleOfEnteringANumber = YES;
    }
}

@end

1 个解决方案

#1

Actually, you're missing brackets. Xcode just assumed you didn't want them since you didn't have an open bracket, so you got the error that you didn't close your parentheses.

实际上,你缺少括号。 Xcode只是假设你不想要它们,因为你没有一个开括号,所以你得到的错误是你没有关闭括号。

if([self userIsInTheMiddleOfEnteringANumber]) {
   ^                                       ^