如何在Python中检查多个异常？

Question

DNASequence =“laksjfklsajdfklsajfklasjfklsad”

    while True:
        lMerLength = input("Please enter the length of the l-mers of the universal array :")
        try:
            if len(DNASequence) >= lMerLength > 0:
                break
        except SyntaxError:
            pass
        #This is not working. How do I check for multiple exceptions in Python?
        except NameError:
            pass
        print "ERROR: Please check your input. You entered an invalid input."

Answer 1

以下是检查多个例外情况的方法。

尝试：

    ..............

除了（SyntaxError，NameError，...）：

    ..............

最后：

    .............

Answer 2

问题是，input返回一个字符串，并将if中的字符串与int进行比较。在python 2.x中，您应该使用raw_input而不是input：

DNASequence = "laksjfklsajdfklsajfklasjfklsad"
while True:
    try:
        lMerLength = int(raw_input("Please enter the length of the l-mers of the universal array :"))
    except ValueError:
        print "ERROR: Please check your input. You entered an invalid input."
        continue
    if len(DNASequence) >= lMerLength > 0:
        break
    print "ERROR: Please check your input. You entered an invalid input."