在Objecttive-C裡建立多執行緒一般有兩種方法， 一種是initWithTarget，還有一種是detachNewThreadSelector。

下面是兩個例項，建立多執行緒的例項,支援傳遞引數.

//
//  main.m
//  initWithTarget
//  Created by exchen on 5/8/15.
//  Copyright (c) 2015 exchen. All rights reserved.
//

#import <Foundation/Foundation.h>

@interface classa : NSObject

-(void)StartThread:(NSString *)str;

@end

@implementation classa

-(void)StartThread:(NSString *)str
{ 
    sleep(3);
    
    NSLog(str);
   
    exit(0);
}

@end

int main(int argc, const char * argv[]) {
    @autoreleasepool {
        // insert code here...
        NSLog(@"Hello, World!");
    }
    
    classa *a = [[classa alloc] init];
    NSThread *thread = [[NSThread alloc] initWithTarget:a selector:@selector(StartThread:) object:@"Start"];
    [thread start];
    
    sleep(5);
    return 0;
}
 

detachNewThreadSelector方式

//
//  main.m
//  TestThread
//
//  Created by exchen on 5/8/15.
//  Copyright (c) 2015 exchen. All rights reserved.
//
#import <Foundation/Foundation.h>

@interface classa : NSObject

-(void)StartThread:(NSString *)str;

@end

@implementation classa

-(void)StartThread:(NSString *)str
{
    NSLog(@"%@",str);
    exit(0);
}

@end

int main(int argc, const char * argv[]) {
    @autoreleasepool {
        // insert code here...
        NSLog(@"Hello, World!");
        
        classa *a = [[classa alloc] init];
        
        [NSThread detachNewThreadSelector:@selector(StartThread:) toTarget:a withObject:@"Start"];
        
        sleep(5);
        
    }
    return 0;
}