INPUT (file statement): Difference between revisions
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{{ | {{PageParameters}} | ||
* {{Parameter|fileNumber&}} is a positive [[LONG]] integer value used to [[OPEN]] the file FOR [[INPUT (file mode)|INPUT]] mode. | * {{Parameter|fileNumber&}} is a positive [[LONG]] integer value used to [[OPEN]] the file FOR [[INPUT (file mode)|INPUT]] mode. | ||
* The [[type]] of the ''variable'' used defines the value or list of values to be returned from the file. Numeric types must match the values returned. | * The [[Variable Types|type]] of the ''variable'' used defines the value or list of values to be returned from the file. Numeric types must match the values returned. | ||
* As reflected in the syntax you can list a number of variables with different types seperated by a comma and they will hold the values in the file (keep in mind that the information in the file should match the variable types used). | * As reflected in the syntax you can list a number of variables with different types seperated by a comma and they will hold the values in the file (keep in mind that the information in the file should match the variable types used). | ||
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{{PageDescription}} | {{PageDescription}} | ||
* The file number can be determined by the programmer or be an unused number returned by the [[FREEFILE]] function. | * The file number can be determined by the programmer or be an unused number returned by the [[FREEFILE]] function. | ||
* Variable types must match the numerical [[type]]s being read. [[STRING]] variables can return unquoted numeric values. | * Variable types must match the numerical [[Variable Types|type]]s being read. [[STRING]] variables can return unquoted numeric values. | ||
* Leading or trailing spaces of [[STRING]] values must be inside of quotes. [[WRITE (file statement)|WRITE #]] writes strings inside of quotes automatically. [[PRINT (file statement)|PRINT #]] removes quotes. | * Leading or trailing spaces of [[STRING]] values must be inside of quotes. [[WRITE (file statement)|WRITE #]] writes strings inside of quotes automatically. [[PRINT (file statement)|PRINT #]] removes quotes. | ||
* [[INPUT #]] will read each value until it encounters a comma for the next value in a list. | * [[INPUT #]] will read each value until it encounters a comma for the next value in a list. | ||
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{{PageSeeAlso}} | {{PageSeeAlso}} | ||
* [[INPUT (file mode)]], [[LINE INPUT (file statement)|LINE INPUT #]], [[INPUT$]] {{ | * [[INPUT (file mode)]], [[LINE INPUT (file statement)|LINE INPUT #]], [[INPUT$]] {{Text|(file input)}} | ||
* [[INPUT]], [[LINE INPUT]], [[INPUT$]] {{ | * [[INPUT]], [[LINE INPUT]], [[INPUT$]] {{Text|(keyboard input)}} | ||
* [[PRINT (file statement)|PRINT #]], [[PRINT USING (file statement)|PRINT #, USING]] | * [[PRINT (file statement)|PRINT #]], [[PRINT USING (file statement)|PRINT #, USING]] | ||
* [[GET|GET #]] | * [[GET|GET #]] |
Latest revision as of 20:25, 26 January 2024
The INPUT # file or port statement reads sequential data using one variable or a comma separated list of matching variable types.
Syntax
- INPUT #fileNumber&, variable1[, variable2, ..., variableN]
Parameters
- fileNumber& is a positive LONG integer value used to OPEN the file FOR INPUT mode.
- The type of the variable used defines the value or list of values to be returned from the file. Numeric types must match the values returned.
- As reflected in the syntax you can list a number of variables with different types seperated by a comma and they will hold the values in the file (keep in mind that the information in the file should match the variable types used).
Description
- The file number can be determined by the programmer or be an unused number returned by the FREEFILE function.
- Variable types must match the numerical types being read. STRING variables can return unquoted numeric values.
- Leading or trailing spaces of STRING values must be inside of quotes. WRITE # writes strings inside of quotes automatically. PRINT # removes quotes.
- INPUT # will read each value until it encounters a comma for the next value in a list.
- Use the EOF function to avoid reading past the end of a file.
- Files created by WRITE # usually have the same number of values on each file line. If INPUT reads more or less values, it may read beyond the end of file or return bad data.
- Use the LINE INPUT (file statement) for files created with PRINT # or PRINT #, USING.
- INPUT can read Excel CSV files, but beware of unquoted text or numerical values containing commas.
Examples
Example 1: Writes new data to a text file sequentially and reads it back to the program screen.
filename$ = "testfile.dat" x = 1: y = 2: z$ = "Three" OPEN filename$ FOR OUTPUT AS #1 'opens and clears an existing file or creates new empty file WRITE #1, x, y, z$ CLOSE #1 PRINT "File created with data. Press a key!" K$ = INPUT$(1) 'press a key OPEN filename$ FOR INPUT AS #2 'opens a file to read it INPUT #2, a, b, c$ CLOSE #2 PRINT a, b, c$ WRITE a, b, c$ END |
1 2 Three 1,2,"Three" |
1,2,"Three" |
- File content: WRITE string values will include quotation marks, but they are not required to read the file value as a string.
Example 2: Commas inside of string values will not affect the INPUT value as those commas are not WRITE separators.
x$ = "Hello, how are you?" y$ = "I'm fine." OPEN "testinp.dat" FOR OUTPUT AS #1 WRITE #1, x$, y$ CLOSE #1 OPEN "testinp.dat" FOR INPUT AS #1 INPUT #1, a$, b$ CLOSE #1 PRINT a$, b$ WRITE a$, b$ |
Hello, how are you? I'm fine. "Hello, how are you?","I'm fine." |
"Hello, how are you?","I'm fine." |
- File content: Commas inside of strings delimited with quotes will be ignored. WRITE will always enclose string values in quotes.
See also
- INPUT (file mode), LINE INPUT #, INPUT$ (file input)
- INPUT, LINE INPUT, INPUT$ (keyboard input)
- PRINT #, PRINT #, USING
- GET #