笔记：long、longlong、int、float、NSString相互转换

nsstring *string = @"123";

// 1.字符串转int
int intstring = [string intvalue];

// 2.int转字符串
nsstring *stringint = [nsstring stringwithformat:@"%d",intstring];

// 3.字符串转float
float floatstring = [string floatvalue];

// 4.float转字符串
nsstring *stringfloat = [nsstring stringwithformat:@"%f",floatstring];


  long longvalue = 104024;    
// 5.long 型转换字符串
 nsnumber *longnumber = [nsnumber numberwithlong:longvalue];
nsstring *longstr = [longnumber stringvalue];
        
 // 6.long long 型转换字符串
nsnumber *longlongnumber = [nsnumber numberwithlonglong:longvalue];
nsstring *longlongstr = [longlongnumber stringvalue];

//7.字符串转long
[str longlongvalue];