这个计算器主要是使用数组进行实现的.虽然没有使用前缀后缀表达式,但是是一种方法o.

.h文件

//
//  LCViewController.h
//  具有优先级的calculator
//
//  Created by lichan on 13-12-4.
//  Copyright (c) 2013年 com.lichan. All rights reserved.
//#import <UIKit/UIKit.h>@interface LCViewController : UIViewController
@property (retain, nonatomic) IBOutlet UITextField *textField;
@property (retain, nonatomic) IBOutlet UITextField *longTextField;@property (strong,nonatomic)NSMutableArray *numbersArray;@property (strong,nonatomic)NSMutableArray *operateArray;@property (copy,nonatomic)NSString *numberTempString;- (IBAction)longTextField:(id)sender;- (IBAction)numberPressed:(id)sender;
- (IBAction)clearScreen:(id)sender;- (IBAction)operatePressed:(UIButton *)sender;
- (IBAction)equalOperate:(id)sender;
@end

.m文件

//
//  LCViewController.m
//  具有优先级的calculator
//
//  Created by lichan on 13-12-4.
//  Copyright (c) 2013年 com.lichan. All rights reserved.
//#import "LCViewController.h"@interface LCViewController ()@end@implementation LCViewController- (void)viewDidLoad
{[super viewDidLoad];_numberTempString = [[NSMutableString alloc]init];_numbersArray = [[NSMutableArray alloc]init];_operateArray = [[NSMutableArray alloc]init];// Do any additional setup after loading the view, typically from a nib.
}-(void)dealloc
{[_numberTempString release];[_textField release];[_numbersArray release];[_operateArray release];[_longTextField release];[super dealloc];}- (void)didReceiveMemoryWarning
{[super didReceiveMemoryWarning];// Dispose of any resources that can be recreated.
}- (IBAction)numberPressed:(id)sender {UIButton *tempButton = (UIButton *)sender;NSString *tempNumber = [tempButton titleLabel].text;//得到button的title值,以便于在textField显示[_textField setText:[NSString stringWithFormat:@"%@%@",_textField.text,tempNumber]];  //textfield 上字符串的连接,以便于形成字符串[_longTextField setText:[NSString stringWithFormat:@"%@%@",_longTextField.text,tempNumber]];_numberTempString = _textField.text;}- (IBAction)clearScreen:(id)sender {[_numbersArray removeAllObjects];[_operateArray removeAllObjects];_numberTempString = nil;[_textField setText:@""];[_longTextField setText:@""];
}- (IBAction)operatePressed:(UIButton *)sender {UIButton *tempButton = (UIButton *)sender;NSString *temp = [tempButton titleLabel].text;//得到button的title值,以便于在textField显示[_longTextField setText:[NSString stringWithFormat:@"%@%@",_longTextField.text,temp]];if (_textField.text != nil) {[_numbersArray addObject:_numberTempString];NSLog(@"---_numbersArray%@",_numbersArray);[_textField setText:@""];[_operateArray addObject:sender.currentTitle];NSLog(@"_operateArray %@",_operateArray);}else if (_textField.text == nil){[_operateArray removeLastObject];[_operateArray addObject:sender.currentTitle];NSLog(@"_operateArray %@",_operateArray);}}- (IBAction)equalOperate:(id)sender {UIButton *tempButton = (UIButton *)sender;NSString *temp = [tempButton titleLabel].text;//得到button的title值,以便于在textField显示[_longTextField setText:[NSString stringWithFormat:@"%@%@",_longTextField.text,temp]];if (_textField.text != nil) {[_numbersArray addObject:_numberTempString];NSLog(@"---_numbersArray%@",_numbersArray);}//----------------
NSString *result = [[NSString alloc]init];while (_numbersArray.count >= 3 )
{NSString *firstOperate = [_operateArray objectAtIndex:0];NSString *sencondOperate = [_operateArray objectAtIndex:1];NSString *firstNumber = [_numbersArray objectAtIndex:0];NSString *sencondNumber = [_numbersArray objectAtIndex:1];NSString *thirdNumber = [_numbersArray objectAtIndex:2];if ([firstOperate isEqualToString:@"+"] ||[firstOperate isEqualToString:@"-"]){if ([sencondOperate isEqualToString:@"*"] ||[sencondOperate isEqualToString:@"/"]){if ([sencondOperate isEqualToString:@"*"]) {result = [self multiOperatorSymbolByOne:sencondNumber Two:thirdNumber];}if ([sencondOperate isEqualToString:@"/"]) {result = [self divOperatorSymbolByOne:sencondNumber Two:thirdNumber];}[_operateArray removeObjectAtIndex:1];[_numbersArray removeObjectAtIndex:2];[_numbersArray replaceObjectAtIndex:1 withObject:result];NSLog(@"num:%@",_numbersArray);}else{NSString *result = [[NSString alloc]init];if ([firstOperate isEqualToString:@"+"]) {result = [self plusOperatorSymbolByOne:firstNumber Two:sencondNumber];}if ([firstOperate isEqualToString:@"-"]) {result = [self subOperatorSymbolByOne:firstNumber Two:sencondNumber];}[_operateArray removeObjectAtIndex:0];[_numbersArray replaceObjectAtIndex:0 withObject:result];[_numbersArray removeObjectAtIndex:1];NSLog(@"%@",_numbersArray);}}else{NSString *firstOperate = [_operateArray objectAtIndex:0];NSString *firstNumber = [_numbersArray objectAtIndex:0];NSString *sencondNumber = [_numbersArray objectAtIndex:1];if ([firstOperate isEqualToString:@"*"]) {result = [self multiOperatorSymbolByOne:firstNumber Two:sencondNumber];}if ([firstOperate isEqualToString:@"/"]) {result = [self divOperatorSymbolByOne:firstNumber Two:sencondNumber];}[_operateArray removeObjectAtIndex:0];[_numbersArray removeObjectAtIndex:1];[_numbersArray replaceObjectAtIndex:0 withObject:result];NSLog(@"%@",_numbersArray);}}NSString *firstOperate = [_operateArray objectAtIndex:0];NSString *firstNumber = [_numbersArray objectAtIndex:0];NSString *sencondNumber = [_numbersArray objectAtIndex:1];NSLog(@"%@",_numbersArray);if ([firstOperate isEqualToString:@"*"]) {result = [self multiOperatorSymbolByOne:firstNumber Two:sencondNumber];}if ([firstOperate isEqualToString:@"/"]) {result = [self divOperatorSymbolByOne:firstNumber Two:sencondNumber];}if ([firstOperate isEqualToString:@"+"]) {result = [self plusOperatorSymbolByOne:firstNumber Two:sencondNumber];}if ([firstOperate isEqualToString:@"-"]) {result = [self subOperatorSymbolByOne:firstNumber Two:sencondNumber];}NSLog(@"result : %@",result);[_longTextField setText:[NSString stringWithFormat:@"%@%@",_longTextField.text,result]];}#pragma mark 操作符号 method- (NSString *)plusOperatorSymbolByOne:(NSString *)str1 Two:(NSString *)str2
{float num1 = [str1 floatValue];float num2 = [str2 floatValue];float resultNum = num1 + num2;return [NSString stringWithFormat:@"%f",resultNum];}- (NSString *)subOperatorSymbolByOne:(NSString *)str1 Two:(NSString *)str2
{float num1 = [str1 floatValue];float num2 = [str2 floatValue];float resultNum = num1 - num2;return [NSString stringWithFormat:@"%f",resultNum];}- (NSString *)multiOperatorSymbolByOne:(NSString *)str1 Two:(NSString *)str2
{float num1 = [str1 floatValue];float num2 = [str2 floatValue];float resultNum = num1 * num2;return [NSString stringWithFormat:@"%f",resultNum];}- (NSString *)divOperatorSymbolByOne:(NSString *)str1 Two:(NSString *)str2
{float num1 = [str1 floatValue];float num2 = [str2 floatValue];float resultNum = num1 / num2;return [NSString stringWithFormat:@"%f",resultNum];}@end