擅长:python、mysql、java
<p>您可以使用<code>try...except</code>检查它是整数还是字母</p>
<pre><code>def input_validation(prompt):
while True:
try:
l = int(input(prompt))
if l<0: #=== If value of l is < 0 like -1,-2
print("Not a positive number.")
else:
break
except ValueError:
print("Your input is invalid.")
print("Try again")
return l
def main():
x = input_validation("Enter a positive number: ")
print (x)
main()
</code></pre>