在python多線程開發中，全局變量是多個線程共享的數據，局部變量是各自線程的，非共享的。

如下幾種寫法都是可以的：

第一種：將列表當成參數傳遞給線程

from threading import Thread
import time

def work1(nums):
    nums.append(44)
    print("----in work1---",nums)

def work2(nums):
    #延時一會，保證t1線程中的事情做完
    time.sleep(1)
    print("----in work2---",nums)

if __name__==‘__main__
 
‘:
    g_nums = [11, 22, 33]

    t1 = Thread(target=work1, args=(g_nums,)) #這種寫法是將列表當成參數傳遞
    t1.start()
    t2 = Thread(target=work2, args=(g_nums,))
    t2.start()

第二種：不傳遞，直接用

from threading import Thread
import time

def work1():
    nums.append(44)
    print("----in work1---",nums)

def work2():
    
 
#延時一會，保證t1線程中的事情做完
    time.sleep(1)
    print("----in work2---",nums)

if __name__==‘__main__‘:
    nums = [11, 22, 33]

    t1 = Thread(target=work1)
    t1.start()
    t2 = Thread(target=work2)
    t2.start()

結果都一樣：

對於參數是字符串，數字這種不可變類型的變量

，改變變量的值的時候，要用上global，否則程序報錯。

from threading import
 
 Thread
import time

def work1():
    global nums
    nums+1
    print("----in work1---",nums)

def work2():
    #延時一會，保證t1線程中的事情做完
    time.sleep(1)
    print("----in work2---",nums)

if __name__==‘__main__‘:
    nums = 12

    t1 = Thread(target=work1)
    t1.start()
    t2 = Thread(target=work2)
    t2.start()

結果：

from threading import Thread
import time

def work1(nums):
    nums=nums+1
    print("----in work1---",nums)

def work2(nums):
    #延時一會，保證t1線程中的事情做完
    time.sleep(1)
    print("----in work2---",nums)

if __name__==‘__main__‘:
    g_nums = 11

    t1 = Thread(target=work1, args=(g_nums,)) 
    t1.start()
    t2 = Thread(target=work2, args=(g_nums,))
    t2.start()

結果：

from threading import Thread
import time

def work1(nums):
    nums+1
    print("----in work1---",nums)

def work2(nums):
    #延時一會，保證t1線程中的事情做完
    time.sleep(1)
    print("----in work2---",nums)

if __name__==‘__main__‘:
    g_nums = 11

    t1 = Thread(target=work1, args=(g_nums,)) 
    t1.start()
    t2 = Thread(target=work2, args=(g_nums,))
    t2.start()

結果：

python線程中的全局變量與局部變量