One 、 Regular expressions

.  ： wildcard , Can identify any character , Represents a character

*  ： Represents the preceding character 0 Times or more

.* ： Find the left boundary value and look for the right boundary right

for example ：<title>.*</title>

？： Non greedy matching , Find the left boundary value and look for the right boundary right , Just find the matching right boundary , Stop looking ; Find the right boundary again 、 Left boundary .

for example ：<title>?*<title>

1. Regular expression extractor

Thread group - add to - Post Processors - Regular expression extractor

Quote name ： Save the variables of the extracted data

Regular expressions ： for example <title>(.*)</title>      The data content to be extracted from the response result （ Parentheses can be used to extract ）

Templates ： $1$    When there are multiple parentheses in the expression , You need to take the first few parentheses to save the variable

Match the Numbers ：1    There are multiple values in parentheses, which one is taken ,1 It means the first one 1 individual ,-1 Express all

The default value ： The value returned when no data is extracted

2. Case a

First visit www.163.com, Will return title Enter the value in Baidu to find

1） Add Netease request （HTTP request + Regular expression extractor ）

 2） Add Baidu request （HTTP request ）

  Be careful ：? The separator is ,s It is equivalent to calling the search module ,/s?wd=" character "

3. Running results

  Two 、xpath Extractor （ The response message is html）

xpath expression

/	Select from root node （ Take the child node ）.
//	Select the node in the document from the current node that matches the selection , Regardless of their location （ Take the descendant node ）.
.	Select the current node .
..	Select the parent of the current node .
@	Select Properties .

Thread group -HTTP request = Post Processors -xpath Extractor

1. Netease request （HTTP+xpath）

2. Baidu requests

3、 ... and 、JSON Extractor （JSON The response message ）

JSON expression

. ： Subelement

Thread group -HTTP request = Post Processors -JSON Extractor

1. Web request

  2. Baidu requests