How to use variables in Python regular expression

Question

i am in need to use a variable in python regular expression

for line in re.findall('(.+)33084-2(.+)', Data):

i am using above code to match a line with 33084-2, some times this values changes so i need to use a variable like

for line in re.findall('(.+)Var_Name(.+)', Data):

please help me how to use a variable in python regular expression

Thanks in advance

Answer 1

If you know that the variable cannot contain any characters with special meaning in a regular expression just use string concatenation or any of the other ways to create a string.

for line in re.findall('(.+)'+Var_Name+'(.+)', Data):

If there is a chance the variable could contain special characters then escape it first:

for line in re.findall('(.+)'+re.escape(Var_Name)+'(.+)', Data):

Answer 2

试试这个简单的方法：

for line in re.findall('(.+){0}(.+)'.format(Var_Name), Data):

Answer 3

使用字符串格式化操作

for line in re.findall('(.+)%s(.+)' % Var_Name, Data):

Answer 4

The first argument to the findall function is just a string. So you use string concatenation:

for line in re.findall('(.+)'+Var_Name+'(.+)', Data):