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- (void)drawRect:(CGRect)rect { [super drawRect:rect]; //步骤一:得到当前绘制画布上下文，用于后续将内容绘制在画布上 CGContextRef context = UIGraphicsGetCurrentContext(); //步骤二：将坐标系上下翻转。对于底层的绘制引擎来说，屏幕左下角是（0，0）坐标。而对于上层的UIKit来说，左上角是（0，0）坐标。所以我们为了之后的坐标系描述按UIKit来显示，这里做了一个坐标系上下翻转操作。翻转之后，底层和上层的（0，0）坐标就是重合的了。 CGContextSetTextMatrix(context, CGAffineTransformIdentity); CGContextTranslateCTM(context, 0, self.bounds.size.height); CGContextScaleCTM(context, 1.0, -1.0); //步骤三：创建绘制区域 CGMutablePathRef path = CGPathCreateMutable(); CGPathAddRect(path, NULL, self.bounds); // CGPathAddEllipseInRect(path, NULL, self.bounds); //步骤四 NSAttributedString *attString = [[NSAttributedString alloc] initWithString:@"ScottZhangScottZhangScottZhangScottZhangScottZhangScottZhangScottZhangScottZhangScottZhangScottZhangScottZhangScottZhangScottZhangScottZhangScottZhangScottZhangScottZhangScottZhangScottZhangScottZhangScottZhangScottZhangScottZhangScottZhangScottZhangScottZhangScottZhangScottZhangScottZhangScottZhangScottZhangScottZhangScottZhangScottZhangScottZhangScottZhangScottZhang"]; CTFramesetterRef framesetter = CTFramesetterCreateWithAttributedString((CFAttributedStringRef)attString); CTFrameRef frame = CTFramesetterCreateFrame(framesetter, CFRangeMake(0, [attString length]), path, NULL); //步骤五 CTFrameDraw(frame, context); //步骤六 CFRelease(frame); CFRelease(path); CFRelease(framesetter);} 转载地址：http://hieym.baihongyu.com/