Objective-C语法之基本数据类型

1、新建项目

为了方便，我们新建一个Single View Application 。

输入项目名称 BaseType

Objective-C语法之基本数据类型

Product Name: 指产品名称，类似于项目名称。
Company Identifier: 公司标识符，一般命名规则为 “com.公司名”
Bundle Identifier: 指包标识符，用于唯一标识应用程序，默认会根据公司标识符和产品名来组合生成
Device Family: 指该应用支持的设备类型，共三个选项：iPhone、iPad、Universal（即iPhone、iPad通用）
Include Unite Tests: 是否包含单元测试代码模板，如果勾选，Xcode会帮助生成单元测试代码模板

在项目里找到，ViewController.m 为了方便演示，在界面启动时，我们加入测试代码

2 、C语言的基本数据类型长度

NSLog(@"The size of an int is: %lu bytes.",sizeof(int));
NSLog(@"The size of a short int is: %lu bytes.",sizeof(short int));
NSLog(@"The size of a long int is: %lu bytes.",sizeof(long int));
NSLog(@"The size of a char is: %lu bytes.",sizeof(char));
NSLog(@"The size of a float is: %lu bytes.",sizeof(float));
NSLog(@"The size of a double is: %lu bytes.",sizeof(double));
NSLog(@"The size of a bool is: %lu bytes.",sizeof(bool)); // Do any additional setup after loading the view,

结果：

2012-06-13 13:55:46.726 BaseType[3032:f803] The size of an int is: 4 bytes.
2012-06-13 13:55:46.726 BaseType[3032:f803] The size of a short int is: 2 bytes.
2012-06-13 13:55:46.727 BaseType[3032:f803] The size of a long int is: 4 bytes.
2012-06-13 13:55:46.731 BaseType[3032:f803] The size of a char is: 1 bytes.
2012-06-13 13:55:46.732 BaseType[3032:f803] The size of a float is: 4 bytes.
2012-06-13 13:55:46.733 BaseType[3032:f803] The size of a double is: 8 bytes.
2012-06-13 13:55:46.733 BaseType[3032:f803] The size of a bool is: 1 bytes.

3、格式化输出数据

//整型
int integerType = 5;
//浮点型
float floatType = 3.1415;
//双浮点型
double doubleType = 2.2033;
//短整型
short int shortType = 200;
//长整型
long long int longlongType = 7758123456767L;
//c语言字符串
char * cstring = "this is a string!";
//整型
NSLog(@"The value of integerType = %d",integerType);
//浮点型
NSLog(@"The value of floatType = %.2f",floatType);
//双浮点型
NSLog(@"The value of doubleType = %e",doubleType);
//短整型
NSLog(@"The value of shortType = %hi",shortType);
//长整型
NSLog(@"The value of longlongType = %lli",longlongType);
//c语言字符串
NSLog(@"The value of cstring = %s",cstring);

结果：

2012-06-13 14:06:18.757 BaseType[3215:f803] The value of integerType = 5
2012-06-13 14:06:18.757 BaseType[3215:f803] The value of floatType = 3.14
2012-06-13 14:06:18.758 BaseType[3215:f803] The value of doubleType = 2.203300e+00
2012-06-13 14:06:18.758 BaseType[3215:f803] The value of shortType = 200
2012-06-13 14:06:18.758 BaseType[3215:f803] The value of longlongType = 7758123456767
2012-06-13 14:06:18.758 BaseType[3215:f803] The value of cstring = this is a string!

Objective-C语法之基本数据类型

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