What are the methods of black box testing? What is the definition?

Black box testing is mainly to test whether the functions of the software can be used normally. In the process of testing, the program is regarded as a black box that cannot be opened. Without considering the internal structure and characteristics of the program, the program is tested through the program interface to check whether the program function can be opened and used normally according to the design requirements and specifications. Black-box testing should be done on the software interface.

1, equivalence class division method:

Equivalence class division is to divide all possible input data into several subsets, and then select several representative data from each subset as test cases. This method is an important and commonly used design method of black box test cases.

2. For example:

For example, the test "Enter three integers"? A, B and C form a triangle as the side lengths of three sides respectively. "

3. Boundary value analysis method:

Boundary condition is the boundary condition where the software runs.

4. Wrong speculation method:

List all possible errors in the program, as well as special cases that are prone to errors.

5. Causality diagram:

Analyze what is the cause and what is the result in the description of the program specification. The reason is usually an input condition or an equivalent class of input conditions. The result is an output condition.

6, judgment table driving method:

The specific value of any combination of conditions and the corresponding action to be performed. The column that runs through the condition items and operation items in the decision table is a rule.

7, flow chart method:

Visualize the function description of the program with flow chart.

8. For example:

Product quality process control

9. Wrong guess:

The wrong method is largely based on experience, and it is based on the analysis of the test results made in the past and the intuitive speculation of the revealed defects.

10, random test method:

A random test is a test without written test cases, recorded expected results, checklists, scripts or instructions.