读取文本文件并将其与python中的字典键进行匹配

Question

I have a dictionary made in python. I also have a text file where each line is a different word. I want to check each line of the text file against the keys of the dictionary and if the line in the text file matches the key I want to write that key's value to an output file. Is there an easy way to do this. Is this even possible? I am new to programming and cannot quite get a handle of how to access the dictionaries. Thank-you for the help.

Answer 1

Read a file line by line like this:

with open(filename, 'r') as f:
    for line in f:
        value = mydict.get(line.strip())
        if value is not None:
            print value

This prints each value to standard output. If you want to output to a file it would be like this:

with open(infilename, 'r') as infile, open(outfilename, 'w') as outfile:
    for line in infile:
        value = mydict.get(line.strip())
        if value is not None:
            outfile.write(value + '\n')

Answer 2

The following code has worked for me.

# Initialize a dictionary
dict = {}

# Feed key-value pairs to the dictionary 
dict['name'] = "Gautham"
dict['stay'] = "Bangalore"
dict['study'] = "Engineering"
dict['feeling'] = "Happy"

# Open the text file "text.txt", whose contents are:
####################################
## what is your name
## where do you stay
## what do you study
## how are you feeling
####################################

textfile = open("text.txt",'rb')

# Read the lines of text.txt and search each of the dictionary keys in every 
# line

for lines in textfile.xreadlines():
    for eachkey in dict.keys():
        if eachkey in lines:
            print lines + " : " + dict[eachkey]
        else:
            continue

# Close text.txt file
textfile.close()