Objective-C中的字符串替换

Question

替换字符的最佳方法是使用Objective-C for iPhone SDK中的字符串？

Answer 1

你可以使用这个方法

- (NSString *)stringByReplacingOccurrencesOfString:(NSString *)target 
                                        withString:(NSString *)replacement

...获取一个替换了子字符串的新字符串(参见NSString其他文档)

使用示例

NSString *str = @"This is a string";

str = [str stringByReplacingOccurrencesOfString:@"string"
                                     withString:@"duck"];

Answer 2

NSString对象是不可变的(它们不能被更改),但是有一个可变的子类NSMutableString,它为您提供了几种替换字符串中字符的方法.这可能是你最好的选择.

Answer 3

如果您想要多个字符串替换:

NSString *s = @"foo/bar:baz.foo";
NSCharacterSet *doNotWant = [NSCharacterSet characterSetWithCharactersInString:@"/:."];
s = [[s componentsSeparatedByCharactersInSet: doNotWant] componentsJoinedByString: @""];
NSLog(@"%@", s); // => foobarbazfoo

Answer 4

它还使用stringByReplacingCharactersInRange:withString替换字符串:

for (int i = 0; i < card.length - 4; i++) {

    if (![[card substringWithRange:NSMakeRange(i, 1)] isEqual:@" "]) {

        NSRange range = NSMakeRange(i, 1);
        card = [card stringByReplacingCharactersInRange:range withString:@"*"];

    }

} //out: **** **** **** 1234