What does “hard coded” mean?

问题

My assignment asks me to access a test.txt document, so the file name has to be hard coded to my C drive. I have no idea what hardcoding means. Can somebody please help me with this?

回答1:

"hard coding" means putting something into your source code. If you are not hard coding, then you do something like prompting the user for the data, or allow the user to put the data on the command line, or something like that.

So, to hard code the location of the file as being on the C: drive, you would just put the pathname of the file all together in your source code.

Here is an example.

int main()
{
    const char *filename = "C:\\myfile.txt";

    printf("Filename is: %s\n", filename);
}

The file name is "hard coded" as: C:\myfile.txt

The reason the backslash is doubled is because backslashes are special in C strings.

回答2:

"Hard Coding" means something that you want to embeded with your program or any project that can not be changed directly. For example if you are using a database server, then you must hardcode to connect your database with your project and that can not be changed by user. Because you have hard coded.

回答3:

Scenario

In a college there are many students doing different courses, and after an examination we have to prepare a marks card showing grade. I can calculate grade two ways

1. I can write some code like this

    if(totalMark <= 100 && totalMark > 90) { grade = "A+"; }
    else if(totalMark <= 90 && totalMark > 80) { grade = "A"; }
    else if(totalMark <= 80 && totalMark > 70) { grade = "B"; }
    else if(totalMark <= 70 && totalMark > 60) { grade = "C"; }

2. You can ask user to enter grade definition some where and save that data

Something like storing into a database table

In the first case the grade is common for all the courses and if the rule changes the code needs to be changed. But for second case we are giving user the provision to enter grade based on their requirement. So the code will be not be changed when the grade rules changes.

That's the important thing when you give more provision for users to define business logic. The first case is nothing but Hard Coding.

So in your question if you ask the user to enter the path of the file at the start, then you can remove the hard coded path in your code.

回答4:

The antonym of Hard-Coding is Soft-Coding. For a better understanding of Hard Coding, I will introduce both terms.

Hard-coding: feature is coded to the system not allowing for configuration;
Parametric: feature is configurable via table driven, or properties files with limited parametric values ;
Soft-coding: feature uses “engines” that derive results based on any number of parametric values (e.g. business rules in BRE); rules are coded but exist as parameters in system, written in script form

Examples:

// firstName has a hard-coded value of "hello world"
string firstName = "hello world";

// firstName has a non-hard-coded provided as input
Console.WriteLine("first name :");
string firstName = Console.ReadLine();

A hard-coded constant^[1]:

float areaOfCircle(int radius)
{
    float area = 0;
    area = 3.14*radius*radius;  //  3.14 is a hard-coded value
    return area;
}

Additionally, hard-coding and soft-coding could be considered to be anti-patterns^[2]. Thus, one should strive for balance between hard and soft-coding.

Hard Coding “Hard coding” is a well-known antipattern against which most web development books warns us right in the preface. Hard coding is the unfortunate practice in which we store configuration or input data, such as a file path or a remote host name, in the source code rather than obtaining it from a configuration file, a database, a user input, or another external source.

The main problem with hard code is that it only works properly in a certain environment, and at any time the conditions change, we need to modify the source code, usually in multiple separate places.

Soft Coding
If we try very hard to avoid the pitfall of hard coding, we can easily run into another antipattern called “soft coding”, which is its exact opposite.

In soft coding, we put things that should be in the source code into external sources, for example we store business logic in the database. The most common reason why we do so, is the fear that business rules will change in the future, therefore we will need to rewrite the code.

In extreme cases, a soft coded program can become so abstract and convoluted that it is almost impossible to comprehend it (especially for new team members), and extremely hard to maintain and debug.

Sources and Citations:

1: Quora: What does hard-coded something mean in computer programming context?
2: Hongkiat: The 10 Coding Antipatterns You Must Avoid

Further Reading:

Software Engineering SE: Is it ever a good idea to hardcode values into our applications?
Wikipedia: Hardcoding
Wikipedia: Soft-coding

回答5:

There are two types of coding.

(1) hard-coding (2) soft-coding

Hard-coding. Assign values to program during writing source code and make executable file of program.Now, it is very difficult process to change or modify the program source code values. like in block-chain technology, genesis block is hard-code that cannot changed or modified.

Soft-coding: it is process of inserting values from external source into computer program. like insert values through keyboard, command line interface. Soft-coding considered as good programming practice because developers can easily modify programs.

来源：https://stackoverflow.com/questions/1895789/what-does-hard-coded-mean

标签

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