步骤：
1.打开Xcode，单机Creat a new Xcode project
2.左边选择ios下Application,右边选择single view Application
3.填写项目名称单机Next
4.ViewController.h中定义成员和方法
//
// ViewController.h
// TestCalculator4
//
// Created by heyonggang on 13-11-28.
// Copyright (c) 2013年 MiracleHe. All rights reserved.
// #import <UIKit/UIKit.h> @interface ViewController : UIViewController @property(retain,nonatomic) UIButton *button;
@property(retain,nonatomic) UILabel *label;
@property(retain,nonatomic) NSMutableString *string; //NSMutableString用来处理可变对象，如需要处理字符串并更改字符串中的字符
@property(assign,nonatomic) double num1,num2;
@property(assign,nonatomic) NSString *str; @end
5.ViewController.m
//
// ViewController.m
// TestCalculator4
//
// Created by heyonggang on 13-11-28.
// Copyright (c) 2013年 MiracleHe. All rights reserved.
// #import "ViewController.h"
#import <QuartzCore/QuartzCore.h> @interface ViewController () @end @implementation ViewController - (void)viewDidLoad
{
[super viewDidLoad]; //创建标签
self.label=[[UILabel alloc]initWithFrame:CGRectMake(, , , )];
[self.view addSubview:_label];
self.label.backgroundColor=[UIColor greenColor]; //设置背景颜色
self.label.textColor=[UIColor blackColor]; //字体颜色
//self.label.textAlignment = UITextAlignmentRight; //字体居右
self.label.textAlignment = NSTextAlignmentCenter;
self.label.font=[UIFont systemFontOfSize:32.4]; //设置字体 //添加1-9数字
NSArray *array=[NSArray arrayWithObjects:@"",@"",@"",@"",@"",@"",@"",@"",@"", nil];
int n=;
for (int i=; i<; i++)
{
for (int j=; j<; j++)
{
self.button=[UIButton buttonWithType:UIButtonTypeRoundedRect];
self.button.frame=CGRectMake(+*j, +*i, , );
[self.button setTitle:[array objectAtIndex:n++] forState:UIControlStateNormal]; //注意：[array objectAtIndex:n++]
[self.view addSubview:_button];
[self.button addTarget:self action:@selector(shuzi:) forControlEvents:UIControlEventTouchUpInside]; //addTarget:self 的意思是说，这个方法在本类中也可以传入其他类的指针
}
} //单独添加0
UIButton *button0=[UIButton buttonWithType:UIButtonTypeCustom]; //创建一个圆角矩形的按钮
/*
CALayer *layer = button0.layer;
[layer setMasksToBounds:YES];
[layer setCornerRadius:5.0];
button0.layer.borderColor = [UIColor lightGrayColor].CGColor;
button0.layer.borderWidth = 1.0f;
*/
[button0 setFrame:CGRectMake(, , , )]; //设置button在view上的位置
//也可以这样用：button0.frame:CGRectMake(30, 345, 60, 60);
[button0 setTitle:@"" forState:UIControlStateNormal]; //设置button主题
button0.titleLabel.textColor = [UIColor blackColor]; //设置0键的颜色
[button0 addTarget:self action:@selector(shuzi:) forControlEvents:UIControlEventTouchUpInside]; //按下按钮，并且当手指离开离开屏幕的时候触发这个事件
//触发了这个事件后，执行shuzi方法，action:@selector(shuzi:)
[self.view addSubview:button0]; //显示控件 //添加运算符
NSArray *array1=[NSArray arrayWithObjects:@"+",@"-",@"*",@"/",nil];
for (int i=; i<; i++)
{
UIButton *button1=[UIButton buttonWithType:UIButtonTypeRoundedRect];
[button1 setFrame:CGRectMake(, +*i, , )];
[button1 setTitle:[array1 objectAtIndex:i] forState:UIControlStateNormal];
//[array1 objectAtIndex:i]为获取按钮的属性值
[self.view addSubview:button1];
[button1 addTarget:self action:@selector(go:) forControlEvents:UIControlEventTouchUpInside];
} //添加=
UIButton *button2=[UIButton buttonWithType:UIButtonTypeRoundedRect];
[button2 setFrame:CGRectMake(, , , )];
[button2 setTitle:@"=" forState:UIControlStateNormal];
[button2 addTarget:self action:@selector(go:) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:button2]; //添加清除键
UIButton *button3=[UIButton buttonWithType:UIButtonTypeRoundedRect];
[button3 setFrame:CGRectMake(, , , )];
[button3 setTitle:@"AC" forState:UIControlStateNormal];
[button3 addTarget:self action:@selector(clean:) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:button3]; //添加.
UIButton *button4=[UIButton buttonWithType:UIButtonTypeRoundedRect];
[button4 setFrame:CGRectMake(, , , )];
[button4 setTitle:@"." forState:UIControlStateNormal];
[button4 addTarget:self action:@selector(shuzi:) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:button4]; //后退
UIButton *button5=[UIButton buttonWithType:UIButtonTypeRoundedRect];
[button5 setFrame:CGRectMake(, , , )];
[button5 setTitle:@"back" forState:UIControlStateNormal];
[button5 addTarget:self action:@selector(back:) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:button5]; self.string=[[NSMutableString alloc]init];//初始化可变字符串，分配内存
self.str = [[NSString alloc]init];
// Do any additional setup after loading the view, typically from a nib.
} //0-9方法
- (void)shuzi:(id)sender
{ [self.string appendString:[sender currentTitle]]; //数字连续输入
self.label.text=[NSString stringWithString:_string]; //显示数值
self.num1=[self.label.text doubleValue]; //保存输入的数值
NSLog(@"self.num1 is %f",self.num1); } //计算方法
-(void)go:(id)sender
{
if ([self.str isEqualToString:@""])//当str里为空
{
self.num2=self.num1;
NSLog(@"self.num2 is %f",self.num2);
self.label.text=[NSString stringWithString:_string]; //只要是符号就显示数值
[self.string setString:@""]; //字符串清零
self.str=[sender currentTitle]; //保存运算符为了作判断作何种运算
NSLog(@"%@",_str);
[self.string appendString:self.str];
self.label.text=[NSString stringWithString:_string]; //显示数值
[self.string setString:@""]; //字符串清零
}
else
{
//输出上次计算结果
if ([self.str isEqualToString:@"+"])//之前的符号是+
{
[self.string setString:@""];//字符串清零
self.num2+=self.num1;//num2是运算符号左边的数值，还是计算结果 //输出上次结果后判断这次输入的是何符号
if ([[sender currentTitle]isEqualToString:@"="])
{
NSLog(@"self.num2 is %f",self.num2);
self.label.text=[NSString stringWithFormat:@"%f",self.num2];
self.str=@"";
}
else if ([[sender currentTitle]isEqualToString:@"+"]||[[sender currentTitle]isEqualToString:@"-"]||[[sender currentTitle]isEqualToString:@"*"]||[[sender currentTitle]isEqualToString:@"/"])
{
NSLog(@"self.num2 is %f",self.num2);
self.label.text=[NSString stringWithFormat:@"%f",self.num2];
[self.string setString:@""]; //字符串清零
self.str=[sender currentTitle];//保存运算符为了作判断作何种运算
NSLog(@"%@",_str);
[self.string appendString:self.str];
[self.string setString:@""];//字符串清零
}
} else if ([self.str isEqualToString:@"-"])//之前的符号是-
{
[self.string setString:@""];//字符串清零
self.num2-=self.num1;
//输出上次结果后判断这次输入的是何符号
if ([[sender currentTitle]isEqualToString:@"="])
{
NSLog(@"self.num2 is %f",self.num2);
self.label.text=[NSString stringWithFormat:@"%f",self.num2];
self.str=@"";
}
else if ([[sender currentTitle]isEqualToString:@"+"]||[[sender currentTitle]isEqualToString:@"-"]||[[sender currentTitle]isEqualToString:@"*"]||[[sender currentTitle]isEqualToString:@"/"])
{
NSLog(@"self.num2 is %f",self.num2);
self.label.text=[NSString stringWithFormat:@"%f",self.num2];
[self.string setString:@""];//字符串清零
self.str=[sender currentTitle];//保存运算符为了作判断作何种运算
NSLog(@"%@",_str);
[self.string appendString:self.str];
[self.string setString:@""];//字符串清零
}
} else if([self.str hasPrefix:@"*"])//之前的符号是* hasPrefix:方法的功能是判断创建的字符串内容是否以某个字符开始
{
[self.string setString:@""];//字符串清零
self.num2*=self.num1;
//输出上次结果后判断这次输入的是何符号
if ([[sender currentTitle] isEqualToString:@"="])
{
NSLog(@"self.num2 is %f",self.num2);
self.label.text=[NSString stringWithFormat:@"%f",self.num2];
self.str=@"";
}
else if ([[sender currentTitle]isEqualToString:@"+"]||[[sender currentTitle]isEqualToString:@"-"]||[[sender currentTitle]isEqualToString:@"*"]||[[sender currentTitle]isEqualToString:@"/"])
{
NSLog(@"self.num2 is %f",self.num2);
self.label.text=[NSString stringWithFormat:@"%f",self.num2];
[self.string setString:@""]; //字符串清零
self.str=[sender currentTitle]; //保存运算符为了作判断作何种运算
NSLog(@"%@",_str);
[self.string appendString:self.str]; //在字符串后增加新的东西，［a appendString:]
[self.string setString:@""]; //字符串清零
}
} else if ([self.str isEqualToString:@"/"])//之前的符号是/
{
[self.string setString:@""];//字符串清零
self.num2/=self.num1;
//判断输出上次结果后判断这次输入的是何符号
if ([[sender currentTitle]isEqualToString:@"="])
{
NSLog(@"self.num2 is %f",self.num2);
self.label.text=[NSString stringWithFormat:@"%f",self.num2];
self.str=@"";
}
else if ([[sender currentTitle]isEqualToString:@"+"]||[[sender currentTitle]isEqualToString:@"-"]||[[sender currentTitle]isEqualToString:@"*"]||[[sender currentTitle]isEqualToString:@"/"])
{
NSLog(@"self.num2 is %f",self.num2);
self.label.text=[NSString stringWithFormat:@"%f",self.num2];
[self.string setString:@""];//字符串清零
self.str=[sender currentTitle];//保存运算符为了作判断作何种运算
NSLog(@"%@",_str);
[self.string appendString:self.str];
[self.string setString:@""];//字符串清零
} }
}
} //当按下清除建时，所有数据清零
-(void)clean:(id)sender
{
[self.string setString:@""];//清空字符
self.num1=;
self.num2=;
self.label.text=@"";//保证下次输入时清零 } //返回键
-(void)back:(id)sender
{
if (![self.label.text isEqualToString:@""])//判断不是空
{
[self.string deleteCharactersInRange:NSMakeRange
([self.string length]-,)];//删除最后一个字符
self.label.text=[NSString stringWithString:_string];//显示结果
}
} - (void)viewDidUnload
{
[super viewDidUnload];
// Release any retained subviews of the main view.
} - (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
return (interfaceOrientation != UIInterfaceOrientationPortraitUpsideDown);
} - (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
} @end