How to compare an ASCII value

c file text ascii file-read
XIIIX picture XIIIX · Sep 19, 2011 · Viewed 59.3k times · Source

I want to store the ASCII value of a letter into a variable, how can I do this?

for example :

r ASCII variable = 82
main()
{
    character = "character read from a file";
    variable= "r ascii"; //(in this case 82), the problem is that the letter is always        variable.;
    printf( "the value of %c is %d, character, variable)
}

How can I do this?

Also on an extra note, how could I read a .txt file character by character? so It could be saved on the character variable.

Answer

Pablo Santa Cruz picture Pablo Santa Cruz · Sep 19, 2011

Just do:

if (r == 82) {
   // provided r is a char or int variable
}

In C, char variables are represented by their ASCII integer value, so, if you have this:

char r;
r = 82;
if (r == 82) {
}

Is the same as:

char r;
r = 'R';
if (r == 'R') { // 'R' value is 82

}

You can even mix them:

char r;
r = 82;
if (r == 'R') { // will be true

}

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