nsstring和const char *转换 [英] nsstring and const char* conversion

问题描述

我尝试将nsstring转换为const char *。

i try to convert nsstring to const char*.

1-我一起添加一个nsstring和一个整数

2-然后我转换这个新的nsstring到const char *

3-我有一个对象，我将这个新的nsstring属性作为我的对象的名字。

4-我在另一个函数中使用这个对象

1- i add a nsstring and an integer together
2- then i convert this new nsstring to const char*
3- i have an object and i attribute this new nsstring as my object's name.
4- i use this object in another function

NSString * firstName = [NSString stringWithFormat：@Name％d，1];

const char * secondName = [ firstName cString];

myobject-> setName（secondName）;

NSString* firstName = [NSString stringWithFormat: @"Name%d", 1];
const char* secondName = [firstName cString];
myobject->setName(secondName);

问题：A
$ b当我在我的函数中使用我的对象时，$ b 1- secondName为null。

2-但如果我将firstName替换为：firstName =Name1;

3-它的工作原理

problem : A
1- secondName is null when i use my object in my function.
2- but if i replace firstName by : firstName = "Name1";
3- it works

问题B

1-如果我替换const char * secondName = [firstName cString];

by const char * secondName = [macString UTF8String];

2-即使我有firstName =Name1;

3-这不起作用!!

problem B
1- if i replace const char* secondName = [firstName cString];
by const char* secondName = [macString UTF8String];
2- even if i have firstName = "Name1";
3- this is not working !!

任何想法??

谢谢

：=）

推荐答案

使用cStringUsingEncoding NSString类：

Use cStringUsingEncoding from the NSString class:

NSString *myString = @"Hello";
const char *cString = [myString cStringUsingEncoding:NSASCIIStringEncoding];

这篇关于nsstring和const char *转换的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！