1. Set Variable
定义：Returns the given values which can then be assigned to a variables.
示例1：
${a} Set Variable 50
示例2：
${traffic_in_xpath}= Set Variable xpath=//table[@id='blocked_services_table']//td[text()='${service_name}']/parent::tr/td[4]
${traffic_in_status} Get Element Attribute ${browser} ${traffic_in_xpath}//input[@type='checkbox']@checked
${traffic_in_checked}= Run Keyword If '${traffic_in_status}'=='None' Set Variable false ELSE Set Variable true
2. Create List
定义：Returns a list containing given items.
示例1：
@{list} Create List a b c
示例2：
: FOR ${index} IN RANGE 5
\ # Verify the connection status
\ ${is_pass} Run Keyword And Ignore Error Should Match Regexp ${result} Connection.*succeeded!
\ # Verify the result
\ Run Keyword If '@{is_pass}[0]'=='${expected_status}' Exit For Loop
3. Evaluate
定义：Evaluates the given expression in Python and returns the results.
示例1：
generate random ip address
[Arguments] ${start} ${stop}
[Documentation] generate random IP address, such as 192.168.1.xxx
[Return] ${r}
${random} Evaluate random.randint(${start},${stop}) random
${r} Set Variable 192.168.1.${random} 示例2：类型转换
${a} Evaluate int(4)
${b} Evaluate int(5)示例3：结果运算
${ns} = Create Dictionary x=${4} y=${2}
${result}= Evaluate x*10 + y namespace=${ns}
Result：
${ns} = {'x': 4, 'y': 2}
${result} = 42
4. Get Variable Value
定义：
Returns variable value or default if the variable does not exist.
示例1：
*** Test Cases ***
test case1 - Run Keyword If
${a} Set Variable 50
Run Keyword If ${a}>=90 Log 优秀
... ELSE IF ${a}>=70 Log 良好
... ELSE IF ${a}>=60 Log 及格
... ELSE Log 不及格
${a_a} Get Variable Value ${a}
log ${a_a}
test case2 - Run Keyword Ignore Error
@{CAPTAINS} Create List Picard Kirk Archer
Run Keyword And Ignore Error Should Be Empty ${CAPTAINS}
Log Reached this point despite of error
@{list} Get Variable Value @{CAPTAINS}
log ${list}
运行结果：
Starting test: Rf Test.Helloworld.test case1 - Run Keyword If
20180519 14:34:58.590 : INFO : ${a} = 50
20180519 14:34:58.592 : INFO : 不及格
20180519 14:34:58.594 : INFO : ${a_a} = 50
20180519 14:34:58.594 : INFO : 50
Ending test: Rf Test.Helloworld.test case1 - Run Keyword If
Starting test: Rf Test.Helloworld.test case2 - Run Keyword Ignore Error
20180519 14:34:58.597 : INFO : @{CAPTAINS} = [ Picard | Kirk | Archer ]
20180519 14:34:58.598 : INFO : Length is 3
20180519 14:34:58.599 : FAIL : '['Picard', 'Kirk', 'Archer']' should be empty.
20180519 14:34:58.601 : INFO : Reached this point despite of error
20180519 14:34:58.602 : INFO : @{list} = [ Picard | Kirk | Archer ]
20180519 14:34:58.603 : INFO : ['Picard', 'Kirk', 'Archer']
Ending test: Rf Test.Helloworld.test case2 - Run Keyword Ignore Error