随机获取验证码

简单封装了一个随机获取验证码；

#import@interface AuthcodeView : UIView

@property (strong, nonatomic) NSArray *dataArray;//字符素材数组

@property (strong, nonatomic) NSMutableString *authCodeStr;//验证码字符串

- (void)getAuthcode;

@end

#import "AuthcodeView.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 4

#define kFontSize [UIFont systemFontOfSize:arc4random() % 5 + 15]

@implementation AuthcodeView

- (instancetype)initWithFrame:(CGRect)frame

{

self = [super initWithFrame:frame];

if (self)

{

self.layer.cornerRadius = 5.0f;

self.layer.masksToBounds = YES;

self.backgroundColor = kRandomColor;

[self getAuthcode];//获得随机验证码

}

return self;

}

#pragma mark 获得随机验证码

- (void)getAuthcode

{

//字符串素材

self.layer.cornerRadius = 3.0f;

self.layer.masksToBounds = YES;

self.backgroundColor = kRandomColor;

_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];

//随机从数组中选取需要个数的字符串，拼接为验证码字符串

for (int i = 0; i < kCharCount; i++)

{

NSInteger index = arc4random() % (_dataArray.count-1);

NSString *tempStr = [_dataArray objectAtIndex:index];

_authCodeStr = (NSMutableString *)[_authCodeStr stringByAppendingString:tempStr];

}

}

#pragma mark 点击界面切换验证码

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event

{

[self getAuthcode];

//setNeedsDisplay调用drawRect方法来实现view的绘制

[self setNeedsDisplay];

}

- (void)drawRect:(CGRect)rect

{

[super drawRect:rect];

//设置随机背景颜色

self.backgroundColor = kRandomColor;

//根据要显示的验证码字符串，根据长度，计算每个字符串显示的位置

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;

//依次绘制每一个字符,可以设置显示的每个字符的字体大小、颜色、样式等

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}];

}

//调用drawRect：之前，系统会向栈中压入一个CGContextRef，调用UIGraphicsGetCurrentContext()会取栈顶的CGContextRef

CGContextRef context = UIGraphicsGetCurrentContext();

//设置线条宽度

CGContextSetLineWidth(context, kLineWidth);

//绘制干扰线

for (int i = 0; i < kLineCount; i++)

{

UIColor *color = kRandomColor;

CGContextSetStrokeColorWithColor(context, color.CGColor);//设置线条填充色

//设置线的起点

pX = arc4random() % (int)rect.size.width;

pY = arc4random() % (int)rect.size.height;

CGContextMoveToPoint(context, pX, pY);

//设置线终点

pX = arc4random() % (int)rect.size.width;

pY = arc4random() % (int)rect.size.height;

CGContextAddLineToPoint(context, pX, pY);

//画线

CGContextStrokePath(context);

}

}

@end