iOS開發-隨機圖片驗證碼

標籤：phi   大小   class   system   ntc   objects   檔案   character   script   

在iOS項目中登入註冊經常會用到隨機驗證碼，尤其是以圖片形式產生的驗證碼，可以減少使用第三方資源的代碼使用，只在本地產生並驗證即可，本文即介紹產生隨機圖片驗證碼的流程，驗證碼包括阿拉伯數字0-9，英文大寫字母A-Z，英文小寫字母a-z，產生的驗證碼區分大小寫。若想改成不區分大小寫，只需要在取碼的時候添加判斷即可。

一、首先建立一個繼承自UIView的類，在.h檔案中添加外界需要的屬性和方法：

@property (strong, nonatomic) NSMutableString *authCodeStr;//驗證碼字串- (void)getAuthcode;

 

二、在.m檔案中添加宏定義：

//背景隨機顏色#define kRandomColorAL  [UIColor colorWithRed:arc4random() % 256 / 256.0 green:arc4random() % 256 / 256.0 blue:arc4random() % 256 / 256.0 alpha:0.5];//幹擾線隨機顏色#define kRandomColor  [UIColor colorWithRed:arc4random() % 256 / 256.0 green:arc4random() % 256 / 256.0 blue:arc4random() % 256 / 256.0 alpha:1];//幹擾線數量#define kLineCount 4//幹擾線寬度#define kLineWidth 1.0//驗證碼數量#define kCharCount 4//驗證碼大小#define kFontSize (arc4random() % 5 + 20)

三、初始化：

- (instancetype)initWithFrame:(CGRect)frame{    self = [super initWithFrame:frame];    if (self)    {        self.layer.cornerRadius = 5.0f;        self.layer.masksToBounds = YES;        self.backgroundColor = kRandomColor;                [self getAuthcode];//獲得隨機驗證碼    }    return self;}

四、擷取隨機驗證碼方法：

#pragma mark 獲得隨機驗證碼- (void)getAuthcode{    //字串素材    _dataArray = [[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",nil];        _authCodeStr = [[NSMutableString alloc] initWithCapacity:kCharCount];    //隨機從數組中選取需要個數的字串，拼接為驗證碼字串    for (int i = 0; i < kCharCount; i++)    {        NSInteger index = arc4random() % (_dataArray.count-1);        NSString *tempStr = [_dataArray objectAtIndex:index];        _authCodeStr = (NSMutableString *)[_authCodeStr stringByAppendingString:tempStr];    }}

五、點擊介面切換驗證碼：

#pragma mark 點擊介面切換驗證碼- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{    [self getAuthcode];        //setNeedsDisplay調用drawRect方法來實現view的繪製    [self setNeedsDisplay];}

六、繪製：

#pragma mark 繪製- (void)drawRect:(CGRect)rect{    [super drawRect:rect];        //設定隨機背景顏色    self.backgroundColor = kRandomColorAL;        //根據要顯示的驗證碼字串，根據長度，計算每個字串顯示的位置    NSString *text = [NSString stringWithFormat:@"%@",_authCodeStr];        CGSize cSize = [@"A" 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];        UIFontDescriptor *attributeFontDescriptor = [UIFontDescriptor fontDescriptorWithFontAttributes:                                                     @{UIFontDescriptorFamilyAttribute: @"Marion",                                                       UIFontDescriptorNameAttribute:@"HanziPenSC-W3",                                                       UIFontDescriptorSizeAttribute: @40.0,                                                       UIFontDescriptorMatrixAttribute:[NSValue valueWithCGAffineTransform:CGAffineTransformMakeRotation(M_1_PI*(arc4random() % 2 ))                                                                                        ]}];        UIFont * font = [UIFont fontWithDescriptor:attributeFontDescriptor size:kFontSize];        UIColor *color = kRandomColor;        [textC drawAtPoint:point withAttributes:@{NSFontAttributeName:font,NSForegroundColorAttributeName:color}];            }            //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();    //設定線條寬度    CGContextSetLineWidth(context, kLineWidth);        //繪製幹擾線    for (int i = 0; i < kLineCount; i++)    {        UIColor *color = kRandomColor;        CGContextSetStrokeColorWithColor(context, color.CGColor);//設定線條填充色                //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);    }}

七、調用，在需要使用驗證碼的類中調用：1、定義屬性：

@property (nonatomic, strong) MaxAuthCodeView * authcodeImage;/**< 驗證碼視圖*/

2、初始化：

self.authcodeImage = [[MaxAuthCodeView alloc] initWithFrame:CGRectMake(50, 100, 120, 60)];    [self.view addSubview:self.authcodeImage];    [self.authcodeImage getAuthcode];

3、擷取驗證碼：

NSLog(@"%@",self.authcodeImage.authCodeStr);

八、希望各位能夠擷取到有用的資訊，謝謝！

demo：https://github.com/MaxLi7681/AuthCode

 

iOS開發-隨機圖片驗證碼