它没有将最后一个单词追加到结果列表中，因为最后一个单词后面没有空格字符。要解决这个问题，您可以在循环后添加一个额外的检查，以便在最后一个单词不为空时将其追加到结果列表中。

def mysplit(strng):
    res = []
    word = ""
    for i in range(len(strng)):
        if strng[i] != " ":
            word += strng[i]
        else:
            if word:  # Add this check to avoid appending empty words
                res.append(word)
                word = ""

    if word:  # Add this check to append the last word if it's not empty
        res.append(word)
        
    return res

print(mysplit("To be or not to be, that is the question"))
print(mysplit("To be or not to be,that is the question"))
print(mysplit("   "))
print(mysplit(" abc "))
print(mysplit(""))

结果：

['To', 'be', 'or', 'not', 'to', 'be,', 'that', 'is', 'the', 'question']
['To', 'be', 'or', 'not', 'to', 'be,that', 'is', 'the', 'question']
[]
['abc']
[]

你不需要使用 range（），因为你可以遍历源字符串而不用担心它的长度。类似这样：

def mysplit(s):
    words = ['']
    for c in s:
        if c == ' ':
            if words[-1]:
                words.append('')
        else:
            words[-1] += c
    return words if words[-1] else words[:-1]

print(mysplit("To be or not to be, that is the question"))
print(mysplit("To be or not to be,that is the question"))
print(mysplit("   "))
print(mysplit(" abc "))
print(mysplit(""))

输出：

['To', 'be', 'or', 'not', 'to', 'be,', 'that', 'is', 'the', 'question']
['To', 'be', 'or', 'not', 'to', 'be,that', 'is', 'the', 'question']
[]
['abc']
[]

这个问题分为两个阶段：左/右 * 条带 * 和 * 分割 *。
在下面的代码是指最相似的原始之一。
来自评论：使用一个扩展字符串，在末尾附加一个额外白色。这将解决只最后一个单词 * 的问题。

def mysplit(strng):
    strng_ = strng + " " # <- extended string
    res = []
    word = ""
    for i in range(len(strng_)):
        if strng_[i] != " ":
            word += strng_[i]
        else:
            res.append(word)
            word = ""
        
    return res

tests = "To be or not to be, that is the question", "  To be or not to be, that is the question   ", " "

for test in tests:
    print(mysplit(test))

这里有一个完整的解决问题的方法.它只需要一个额外的检查.

def mysplit(strng):
    strng_ = strng + " " # <- extended string
    res = []
    word = ""
    for i in range(len(strng_)):
        if strng_[i] != " ":
            word += strng_[i]
        else:
            # check empty word
            if word:
                res.append(word)
            word = ""
        
    return res

这里是另一个完整的解决方案，这是基于一个DIY的左/右条

def mysplit(text):
    # left-strip
    c = 0
    for char in text:
        if char == " ":
            c += 1
        else:
            break

    # right-strip
    # reversed string
    text_ = text[c:][::-1]
    c = 0
    for char in text_:
        if char == " ":
            c += 1
        else:
            break

    # striped string
    text_ = text_[c:][::-1]
    
    # check empty string
    if not text_:
        return []
    
    # DIY-split
    text_ += " " # <- extended string
    res = []
    word = ""
    for i in range(len(text_)):
        if text_[i] != " ":
            word += text_[i]
        else:
            res.append(word)
            word = ""
        
    return res

备注：str.isspace可代替str == " "