IOS 產生本地驗證碼，IOS產生驗證碼

IOS 產生本地驗證碼，IOS產生驗證碼

　　在應用程式註冊、登陸或者有關支付確認的介面，經常會用到驗證碼，驗證碼有的是通過手機發送擷取的，有的是在本地點擊擷取的，通過手機發送擷取的動態驗證碼可以使用第三方類庫實現，本地點擊擷取的是在本地自己繪製的，下面我們來詳細講解一下本地產生動態驗證碼的過程。

 

<一>匯入CoreGraphics.framework

 

<二>驗證碼封裝了一個UIView，在使用的時候直接把這個View加到介面上使用

　　CaptchaView.h

#import <UIKit/UIKit.h>@interface CaptchaView : UIView@property (nonatomic, retain) NSArray *changeArray; //字元素材數組@property (nonatomic, retain) NSMutableString *changeString;  //驗證碼的字串@end

　　CaptchaView.m

#import "CaptchaView.h"#define kRandomColor  [UIColor colorWithRed:arc4random() % 256 / 256.0 green:arc4random() % 256 / 256.0 blue:arc4random() % 256 / 256.0 alpha:1.0];#define kLineCount 6#define kLineWidth 1.0#define kCharCount 6#define kFontSize [UIFont systemFontOfSize:arc4random() % 5 + 15]@implementation CaptchaView@synthesize changeString,changeArray;- (instancetype)initWithFrame:(CGRect)frame{    if (self = [super initWithFrame:frame]) {                self.layer.cornerRadius = 5.0; //設定layer圓角半徑        self.layer.masksToBounds = YES; //隱藏邊界        self.backgroundColor = kRandomColor;                //顯示一個隨機驗證碼        [self changeCaptcha];    }        return self;}#pragma mark 更換驗證碼,得到更換的驗證碼的字串-(void)changeCaptcha{//<一>從字元數組中隨機抽取相應數量的字元，組成驗證碼字串    //數組中存放的是全部可選的字元，可以是字母，也可以是中文    self.changeArray = [[NSArray alloc] initWithObjects:@"0",@"1",@"2",@"3",@"4",@"5",@"6",@"7",@"8",@"9",@"A",@"B",@"C",@"D",@"E",@"F",@"G",@"H",@"I",@"J",@"K",@"L",@"M",@"N",@"O",@"P",@"Q",@"R",@"S",@"T",@"U",@"V",@"W",@"X",@"Y",@"Z",@"a",@"b",@"c",@"d",@"e",@"f",@"g",@"h",@"i",@"j",@"k",@"l",@"m",@"n",@"o",@"p",@"q",@"r",@"s",@"t",@"u",@"v",@"w",@"x",@"y",@"z",@"傑",@"瑞",@"教",@"育",nil];        //如果能確定最大需要的容量，使用initWithCapacity:來設定，好處是當元素個數不超過容量時，添加元素不需要重新分配記憶體    NSMutableString *getStr = [[NSMutableString alloc] initWithCapacity:kCharCount];    self.changeString = [[NSMutableString alloc] initWithCapacity:kCharCount];        //隨機從數組中選取需要個數的字元，然後拼接為一個字串    for(int i = 0; i < kCharCount; i++)    {        NSInteger index = arc4random() % ([self.changeArray count] - 1);        getStr = [self.changeArray objectAtIndex:index];                self.changeString = (NSMutableString *)[self.changeString stringByAppendingString:getStr];    }    //<2>從網路擷取字串，然後把得到的字串在本地繪製出來（網路擷取步驟在這省略）//    self.changeString = [NSMutableString stringWithString:@"傑瑞教育"];}#pragma mark 點擊view時調用，因為當前類自身就是UIView，點擊更換驗證碼可以直接寫到這個方法中，不用再額外添加手勢-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{    //點擊介面，切換驗證碼    [self changeCaptcha];        //setNeedsDisplay調用drawRect方法來實現view的繪製    [self setNeedsDisplay];}#pragma mark 繪製介面（1.UIView初始化後自動調用； 2.調用setNeedsDisplay方法時會自動調用）- (void)drawRect:(CGRect)rect {    // 重寫父類方法，首先要調用父類的方法    [super drawRect:rect];    //設定隨機背景顏色    self.backgroundColor = kRandomColor;        //獲得要顯示驗證碼字串，根據長度，計算每個字元顯示的大概位置    NSString *text = [NSString stringWithFormat:@"%@",self.changeString];    CGSize cSize = [@"S" sizeWithAttributes:@{NSFontAttributeName:[UIFont systemFontOfSize:20]}];    int width = rect.size.width / text.length - cSize.width;    int height = rect.size.height - cSize.height;    CGPoint point;        //依次繪製每一個字元,可以設定顯示的每個字元的字型大小、顏色、樣式等    float pX, pY;    for (int i = 0; i < text.length; i++)    {        pX = arc4random() % width + rect.size.width / text.length * i;        pY = arc4random() % height;        point = CGPointMake(pX, pY);        unichar c = [text characterAtIndex:i];        NSString *textC = [NSString stringWithFormat:@"%C", c];                [textC drawAtPoint:point withAttributes:@{NSFontAttributeName:kFontSize}];    }        //調用drawRect：之前，系統會向棧中壓入一個CGContextRef，調用UIGraphicsGetCurrentContext()會取棧頂的CGContextRef    CGContextRef context = UIGraphicsGetCurrentContext();    //設定畫線寬度    CGContextSetLineWidth(context, kLineWidth);        //繪製幹擾的彩色直線    for(int i = 0; i < kLineCount; i++)    {        //設定線的隨機顏色        UIColor *color = kRandomColor;        CGContextSetStrokeColorWithColor(context, [color CGColor]);        //設定線的起點        pX = arc4random() % (int)rect.size.width;        pY = arc4random() % (int)rect.size.height;        CGContextMoveToPoint(context, pX, pY);        //設定線終點        pX = arc4random() % (int)rect.size.width;        pY = arc4random() % (int)rect.size.height;        CGContextAddLineToPoint(context, pX, pY);        //畫線        CGContextStrokePath(context);    }}@end

<三>在介面上添加驗證碼

 　　ViewController.m

#import "ViewController.h"#import "CaptchaView.h"@interface ViewController ()<UITextFieldDelegate,UIAlertViewDelegate>{    CaptchaView *_captchaView;    UITextField *_input;}@end@implementation ViewController- (void)viewDidLoad {    [super viewDidLoad];        //顯示驗證碼介面    _captchaView = [[CaptchaView alloc] initWithFrame:CGRectMake(20, 40, 150, 40)];    [self.view addSubview:_captchaView];        //提示文字    UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(190, 40, 100, 40)];    label.text = @"點擊圖片換驗證碼";    label.font = [UIFont systemFontOfSize:12];    label.textColor = [UIColor grayColor];    [self.view addSubview:label];        //添加輸入框    _input = [[UITextField alloc] initWithFrame:CGRectMake(20, 100, 150, 40)];    _input.layer.borderColor = [UIColor lightGrayColor].CGColor;    _input.layer.borderWidth = 2.0;    _input.layer.cornerRadius = 5.0;    _input.font = [UIFont systemFontOfSize:21];    _input.placeholder = @"請輸入驗證碼!";    _input.clearButtonMode = UITextFieldViewModeWhileEditing;    _input.backgroundColor = [UIColor clearColor];    _input.textAlignment = NSTextAlignmentCenter;    _input.returnKeyType = UIReturnKeyDone;    _input.delegate = self;    [self.view addSubview:_input];}#pragma mark 輸入框協議中方法,點擊return按鈕- (BOOL)textFieldShouldReturn:(UITextField *)textField{    //判斷輸入的是否為驗證圖片顯示的驗證碼    if ([_input.text isEqualToString:_captchaView.changeString]) {        //正確彈出警告款提示正確        UIAlertView *alview = [[UIAlertView alloc] initWithTitle:@"恭喜您 ^o^" message:@"驗證成功" delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil, nil];        [alview show];    }    else    {        //驗證不匹配，驗證碼和輸入框晃動        CAKeyframeAnimation *anim = [CAKeyframeAnimation animationWithKeyPath:@"transform.translation.x"];        anim.repeatCount = 1;        anim.values = @[@-20, @20, @-20];        [_captchaView.layer addAnimation:anim forKey:nil];        [_input.layer addAnimation:anim forKey:nil];    }    return YES;}#pragma mark 警告框中方法-(void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex{    //清空輸入框內容，收回鍵盤    if (buttonIndex==0) {        _input.text = @"";        [_input resignFirstResponder];    }}@end

 

　　想要瞭解更多內容的小夥伴，可以點擊查看源碼，親自運行測試。

 

作者：傑瑞教育
出處：http://www.cnblogs.com/jerehedu/ 
本文著作權歸煙台傑瑞教育科技有限公司和部落格園共有，歡迎轉載，但未經作者同意必須保留此段聲明，且在文章頁面明顯位置給出原文串連，否則保留追究法律責任的權利。