UIBezierPath*bezierPath = [UIBezierPathbezierPath];

//M_PI_2二分之PI

[bezierPathaddArcWithCenter:CGPointMake(150,150)radius:100startAngle:M_PI_2*3endAngle:0clockwise:YES];

[bezierPathaddLineToPoint:CGPointMake(150,150)];

[bezierPathclosePath];

[bezierPathmoveToPoint:CGPointMake(150,150+100)];

[bezierPathaddArcWithCenter:CGPointMake(150,150)radius:100startAngle:M_PI_2endAngle:M_PIclockwise:YES];

[bezierPathaddLineToPoint:CGPointMake(150,150)];

[bezierPathclosePath];

bezierPath.lineWidth=5;

//[[UIColor redColor]setStroke];

//[bezierPath stroke];

[[UIColorgreenColor]setFill];

[bezierPathfill];