使用正则表达式在NSString中查找/替换子字符串

我想使用正则表达式来查找正则表达式模式的每个实例Ie &*; 在我的字符串中，并从中删除，返回值是没有任何匹配的原始字符串。 也希望使用相同的功能来匹配单词之间的多个空格，并改为使用单个空格。 找不到这样的功能。

示例输入字符串

NSString *str = @"123 &1245; Ross Test  12";

返回值应该是

123 Ross Test 12

如果有任何匹配这种模式的东西"&*或多个空格，并用@"";替换它@"";

---

NSString *string = @"123 &1245; Ross Test 12";
NSError *error = nil;
NSRegularExpression *regex = [NSRegularExpression regularExpressionWithPattern:@"&[^;]*;" options:NSRegularExpressionCaseInsensitive error:&error];
NSString *modifiedString = [regex stringByReplacingMatchesInString:string options:0 range:NSMakeRange(0, [string length]) withTemplate:@""];
NSLog(@"%@", modifiedString);

---

在String扩展中使用正则表达式替换代码的字符串

Objective-C的

@implementation NSString(RegularExpression)

- (NSString *)replacingWithPattern:(NSString *)pattern withTemplate:(NSString *)withTemplate error:(NSError **)error {
    NSRegularExpression *regex = [NSRegularExpression regularExpressionWithPattern:pattern
                                                                           options:NSRegularExpressionCaseInsensitive
                                                                             error:error];
    return [regex stringByReplacingMatchesInString:self
                                           options:0
                                             range:NSMakeRange(0, self.length)
                                      withTemplate:withTemplate];
}

@end

解决

NSString *string = @"123 &1245; Ross Test  12";
// remove all matches string
NSString *result = [string replacingWithPattern:@"&[d]+?;" withTemplate:@"" error:nil];
// result = "123  Ross Test  12"

或者更多

NSString *string = @"123 +   456";
// swap number
NSString *result = [string replacingWithPattern:@"([d]+)[ +]+([d]+)" withTemplate:@"$2 + $1" error:nil];
// result = 456 + 123

Swift2

extension String {
    func replacing(pattern: String, withTemplate: String) throws -> String {
        let regex = try NSRegularExpression(pattern: pattern, options: .CaseInsensitive)
        return regex.stringByReplacingMatchesInString(self, options: [], range: NSRange(0..<self.utf16.count), withTemplate: withTemplate)
    }
}

Swift3

extension String {
    func replacing(pattern: String, withTemplate: String) throws -> String {
        let regex = try RegularExpression(pattern: pattern, options: .caseInsensitive)
        return regex.stringByReplacingMatches(in: self, options: [], range: NSRange(0..<self.utf16.count), withTemplate: withTemplate)
    }
}

使用

var string = "1!I 2"want 3#to 4$remove 5%all 6&digit and a char right after 7'from 8(string"
do {
    let result = try string.replacing("[d]+.", withTemplate: "")
} catch {
    // error
}
// result = "I want to remove all digit and a char right after from string"

链接地址: http://www.djcxy.com/p/13461.html

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