word = "some string"
file1 = open("songs.txt", "r")
flag = 0
index = 0
for line in file1:
    index  = 1
    if word in line:
        flag = 1
        break
    if flag == 0:
        print(word   " not found")
    else:

#I would like to print not only the line that has the string, but also the previous and next lines print(?) print(line) print(?)
file1.close()

CodePudding user response：

Use contents = file1.readlines() which converts the file into a list.

Then, loop through contents and if word is found, you can print contents[i], contents[i-1], contents[i 1]. Make sure to add some error handling if word is in the first line as contents[i-1] would throw and error.

CodePudding user response：

word = "some string"
file1 = open("songs.txt", "r")
flag = 0
index = 0
previousline = ''
nextline = ''

for line in file1:
    index  = 1
    if word in line:
        finalindex = index
        finalline = line
        flag = 1
    elsif flag==1
        print(previousline   finalline   line)
        print(index-1   index   index 1)
    else
        previousline = line

You basically already had the main ingredients:

• you have line (the line you currently evaluate)
• you have the index (index)

the todo thus becomes storing the previous and next line in some variable and then printing the results.

have not tested it but code should be something like the above.....

splitting if you find the word, if you have found it and you flagged it previous time and if you have not flagged it.

i believe the else-if shouldnt fire unless flag ==1