如何在python中判断一个字符串是否可以转换为数字

str1 = '1'

str2 = '2.1'

str3 = '三'

str4 = '3.3.3.3'

print(str1.isdigit())

print(str2.isdigit())

print(str3.isdigit())

print(str4.isdigit())

True
False
False
False

str1 = '1'

str2 = '2.1'

str3 = '三'

str4 = '3.3.3.3'

print(str1.isdecimal())

print(str2.isdecimal())

print(str3.isdecimal())

print(str4.isdecimal())

True
False
False
False

str1 = '1'

str2 = '2.1'

str3 = '三'

str4 = '3.3.3.3'

print(str1.isnumeric())

print(str2.isnumeric())

print(str3.isnumeric())

print(str4.isnumeric())

True
False
True
False

def is_number(s):
    try:
        float(s)
        return True
    except ValueError:
        pass
 
    try:
        import unicodedata
        unicodedata.numeric(s)
        return True
    except (TypeError, ValueError):
        pass
 
    return False