嗨，朋友们，我想在表格视图单元格中显示信用卡号，所以我只想显示最后四个字符，例如XXXXXXXXXX1111，第一个字符被x或其他字符替换，我该怎么办？
我已经尝试过波纹管
NSString *CardNumber = [CardNumberValues objectAtIndex:indexPath.row];
NSRange subStringRange = NSMakeRange(0,[CardNumber length]-4);
NSMutableCharacterSet *NumSet = [NSMutableCharacterSet characterSetWithRange:subStringRange];
CardNumber = [[CardNumber componentsSeparatedByCharactersInSet:NumSet] componentsJoinedByString:@"X"];
cell.CardNumber.text = CardNumber;
但它不能正常工作，你可以建议任何参考或代码...
最佳答案
用这个
NSString *CardNumber = @"12345678901234";
NSString *str_padding=@"";
NSRange subStringRange = NSMakeRange(0,[CardNumber length]-4);
str_padding =[str_padding stringByPaddingToLength:subStringRange.length withString:@"X" startingAtIndex:0];
CardNumber = [CardNumber stringByReplacingOccurrencesOfString:[NSString stringWithFormat:@"%@",[CardNumber substringToIndex:subStringRange.length]] withString:str_padding];
NSLog(@"%@",CardNumber);