在Objective-C

Question

如果变量不是nil，我想从变量连接一些字符串。如果他们是零，我不想包括他们。下面的代码可以工作，但是很笨拙，并且随着其他变量的增加而成比例地增加。任何人都可以推荐一种更优雅的方式来做到这一点吗？

NSString *city = self.address.city== nil ? @"" : self.address.city;
NSString *state = self.address.state== nil ? @"" : self.address.state;
NSString *zip = self.address.zip== nil ? @"" : self.address.zip;
NSString *bestCity;

if (city.length>0&&state.length>0&&zip.length>0) {
     bestCity = [NSString stringWithFormat: @"%@ %@ %@", city, state,zip];
}
else if (city.length>0&&state.length>0) {
    bestName = [NSString stringWithFormat: @"%@ %@", city,state];
}
else if (city.length>0&&zip.length>0) {
    bestCity = [NSString stringWithFormat: @"%@ %@", city,zip];
}
else if (city.length>0&&zip.length>0) {
    bestCity = [NSString stringWithFormat: @"%@ %@", city,zip];
}
else if (city.length>0) {
    bestCity = [NSString stringWithFormat: @"%@", city];
}
else if (state.length>0) {
    bestCity = [NSString stringWithFormat: @"%@", state];
}
else if (zip.length>0) {
    bestCity = [NSString stringWithFormat: @"%@", zip];
}
else {
    bestCity = @"";
}

Answer 1

${DESTDIR}

Answer 2

我通常会这样做：

NSMutableArray *bestCityArr = [@[] mutableCopy]; // [[NSMutableArray alloc] init];

if (city.length > 0)
    [bestCityArr addObject:city];

if (state.length > 0)
    [bestCityArr addObject:state];

if (zip.length > 0)
    [bestCityArr addObject:zip];

NSString *bestCity = [bestCityArr componentsJoinedByString:@" "];

Answer 3

此代码可以为您提供帮助！

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