ios – 为UITextField实现输入掩码

我能够使用UITextField子类获得所有这些功能.您可能希望将这些委托方法移动到ViewController中并在那里设置自定义TextField委托.为了这个例子,更容易向你展示一个类中的所有内容.显然,您将不得不调整那些允许满足您需求的字符集.

#import "TextField.h"

@interface TextField()<UITextFieldDelegate>

@end

@implementation TextField

-(instancetype)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];
    if (self) {
        self.delegate = self;
    }
    return self;
}

- (UITextPosition *)closestPositionToPoint:(CGPoint)point{
    UITextPosition *beginning = self.beginningOfDocument;
    UITextPosition *end = [self positionFromPosition:beginning offset:self.text.length];
    return end;
}

- (BOOL)canPerformAction:(SEL)action withSender:(id)sender
{
    if (action == @selector(paste:)
        || action == @selector(select:)
            || action == @selector(selectAll:)
                || action == @selector(cut:)){
        return NO;
    }
    return [super canPerformAction:action withSender:sender];
}

-(BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
    if (range.location == 0 && [string rangeOfCharacterFromSet:[NSCharacterSet letterCharacterSet]].location == NSNotFound) {
        return NO;
    }else if (range.location == 1 && [string rangeOfCharacterFromSet:[NSCharacterSet decimalDigitCharacterSet]].location == NSNotFound){
        return NO;
    }

    return YES;
}

@end