Reading data from SD CARD .txt file, last byte wrong

hello trying read number sd card .txt file. used function below data last byte wrong. number 2345.

code: [select]


float test = 0.0; //global variable

//inside setup() below

file textdata = sd.open("something.txt");
if(textdata)
{
   while(textdata.available())
   {
     float textread = textdata.read() - '0';
     test = test * 10 + textread;
    }
}


the number 234112.00.
then noticed in .txt file. after 2345 there empty line.

quote

2345
<-- empty line here

when deleted empty line got exact number (2345.00).

does empty line return w/c messed first result?

quote

does empty line return w/c messed first result?

yes; read data , includes carriage return and/or line feed.

solution: read databyte variable, check if it's not '\r' or '\n' , next add test variable (after subtracting '0').

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