程序分析：python去除文件中註釋（"//"，"/* */"）和空格

    上一篇中提到了提取數據文件的操作；對於提取的文件，我們還需要做一些處理步驟，在這裏我們是對solidity語言的註釋和空格的處理，solidity語言和大部分語言的註釋一樣也是"//"和"/* */"，同時我們還需要處理刪除註釋部分的空格。

（1）Handle Comment of solidity source code file("//")

# The comment of file will be deleted if exist lines[i]
def Handle_single_comment(lines, i):
    index = lines[i].find("//")
    if index != -1:
        # lines[i] = lines[i][0:index]
        lines[i] = lines[i].replace(lines[i], '', 1)
        lines[i] += ''

（2）Handle Comment of solidity source code file("/* */")

# @return -1:the Line is Comment Line,should delete this line
# @return -2:Only begin Comment found in this Line
# @return  0:Not find Comment
def Handle_document_comment(lines, i):
    global flag
    while True:
        if not flag:
            index = lines[i].find("/*")
            if index != -1:
                flag = True
                index2 = lines[i].find("*/", index + 2)
                if index2 != -1:
                    lines[i] = lines[i].replace(lines[i], '', 1)
                    flag = False  # continue look for comment
                else:
                    lines[i] = lines[i].replace(lines[i], '', 1)  # only find "begin comment
                    lines[i] += ''
                    return -2
            else:
                return 0  # not find
        else:
            index2 = lines[i].find("*/")
            if index2 != -1:
                flag = False
                lines[i] = lines[i].replace(lines[i], '', 1)  # continue look for comment
            else:
                return -1  # should delete this

（3）Remove Comment of file

# At last print the handled result
def RemoveComment(file):
    global flag
    f = open(file, "r")
    lines = f.readlines()
    f.close()
    length = len(lines)
    i = 0
    while i < length:
        ret = Handle_document_comment(lines, i)
        if ret == -1:
            if flag == False:
                print("There must be some wrong")
            del lines[i]
            i -= 1
            length -= 1
        elif ret == 0:
            Handle_single_comment(lines, i)
        else:
            pass
        i += 1

（4）write result back to file

def writeResult(file, lines):
    f = open(file, "w")
    for line in lines:
        if line == '':  # 遇到空格忽略，跳出該次循環
            continue
        f.write(line)
    f.close()

（5）print result

def Output(lines):
    for line in lines:
        if line == '':
            continue
        print(line)

以上步驟可以解決去除代碼源文件中註釋（"//"，"/* */"）和空格。

完整的可運行的代碼可見：https://github.com/Messi-Q/SmartContract-Detection-Based-DeepLearning/blob/master/tools/remove_comment.py.