UITextField 只能輸入字母、數字的方法小結

引入

在IOS實際開發中有些UITextField須要限制輸入內容，如帳號、密碼等，下面簡單介紹其簡單的實現方法，以下：

代碼實現

//定義宏（限制輸入內容）

#define kAlphaNum   @"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"

#define kAlpha      @"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz "

#define kNumbers     @"0123456789"

#define kNumbersPeriod  @"0123456789."

 

//定義UITextFiled的代理方法：

- (BOOL)textField:(UITextField *)textField

    shouldChangeCharactersInRange:(NSRange)range

    replacementString:(NSString *)string {

   

    NSCharacterSet *cs;

    cs = [[NSCharacterSet characterSetWithCharactersInString:kAlphaNum] invertedSet];

    NSString *filtered =

    [[string componentsSeparatedByCharactersInSet:cs] componentsJoinedByString:@""];

    BOOL basic = [string isEqualToString:filtered];

    return basic;

}