Python while循环，,while循环语法结

Python while循环，,while循环语法结

while循环语法结构

当需要语句不断的重复执行时,可以使用while循环while expression： while_suite语句while_suite会连续不断的循环执行,直到表达式的值变成0或false

#!/usr/bin/env pythonsum100 = 0counter = 1while counter <= 100:    sum100 += counter    counter += 1print "result is %d" % sum100

break语句

break语句可以结束当前循环然后跳转到下条语句写程序的时候,应尽量避免重复的代码,在这种情况下可以使用while-break结构

#!/usr/bin/env pythonwhile True:    yn = raw_input("continue?(y/n)")    if yn in ‘Yy‘:        break    print "work on"/usr/bin/python2.6 /root/PycharmProjects/untitled10/break1.pycontinue?(y/n)nwork oncontinue?(y/n)yProcess finished with exit code 0

continue语句

当遇到continue语句时,程序会终止当前循环,并忽略剩余的语句.然后回到循环的顶端如果仍然满足循环条件，循环体内语句继续执行，否则退出循环所有偶数的和

#!/usr/bin/env pythonsum100 = 0counter = 1while counter <= 100:    counter += 1    if counter % 2 == 1:        continue    sum100 += counterprint sum100

else语句

python中的while语句也支持else子句else子句只在循环完成后执行break语句也会跳过else块

#!/usr/bin/env pythonsum10 = 0i = 1while i <= 10:    sum10 += i    i += 1else:    print sum10

Python while循环