objective-C 的Hello World

代码如下：

//  main.m
//  HelloWorld
//  Created by jimmy.yang on 11-1-24.
//  Copyright 2011 __MyCompanyName__. All rights reserved.
 
#import 
 
//定义“几何形状类型”枚举
typedef enum{
    kCircle,
    kRectangle,
    kOblatesShperoid    
} ShapeType;
 
//定义“几何形状颜色”枚举
typedef enum{
    kRedColor,
    kGreenColor,
    kBlueColor
} ShapeColor;
 
//定义“几何形状矩形区域”结构
typedef struct{
    int x,y,width,height;
} ShapeRect;
 
 
//定义“几何形状”结构
typedef struct{
    ShapeType type;
    ShapeColor fillColor;
    ShapeRect bounds;
}Shape;
 
 
//返回“枚举颜色”的名称
NSString *colorName(ShapeColor colorName){
    switch (colorName) {
        case kRedColor:
            return @"red";
            break;
        case kGreenColor:
            return @"green";
            break;  
        case kBlueColor:
            return @"blue";
            break;  
        default:
            return @"no clue";
            break;
    }
}//colorName
 
//画圆
void drawCircle(ShapeRect bounds,ShapeColor fillColor){
    NSLog(@"drawing a circle at (%d,%d,%d,%d) in %@",bounds.x,bounds.y,bounds.width,bounds.height,colorName(fillColor));
}//drawCircle
 
//画矩形
void drawRectangle(ShapeRect bounds,ShapeColor fillColor){
    NSLog(@"drawing a rectangle at (%d,%d,%d,%d) in %@",bounds.x,bounds.y,bounds.width,bounds.height,colorName(fillColor));
}//drawRectangle
 
//画椭圆形
void drawEgg(ShapeRect bounds,ShapeColor fillColor){
    NSLog(@"drawing an egg at (%d,%d,%d,%d) in %@",bounds.x,bounds.y,bounds.width,bounds.height,colorName(fillColor));
}//drawEgg
 
//画几何形状
void drawShapes(Shape shapes[],int count){
    int i;
    for(i=0;i
Console窗口的运行结果：
2011-01-25 13:49:05.978 HelloWorld[734:a0f] drawing a circle at (0,0,10,30) in red
2011-01-25 13:49:06.016 HelloWorld[734:a0f] drawing a rectangle at (30,40,50,60) in green
2011-01-25 13:49:06.018 HelloWorld[734:a0f] drawing an egg at (15,18,37,39) in blue