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Reading A File

Reading a file means extracting the characters that are in the file and loading the data into the memory buffer. To read a file, you must

  • Determine how many characters to read
  • Provide variables to receive the data

VB provides several functions and statements to read a sequential file:

  •  Input 
  •  Input # 
  •  Line Input # 

Input function

this function returns a string containing characters from a file opened in Input or Binary mode.

Input(number, [#]filenumber)

number: specifying the number of characters to return
filenumber: Any valid file number.

The following code segment reads 10 characters into the string variable LastName:

LastName = Input(10, #1)

Input # Function

The Input # statement reads data from an open sequential file and assigns the data to variables.

Input #filenumber, varlist

Assume that the file contains the following: Amit, Sumit. Using the following statement the data can be read into local variables Name1 and Name2:

Input #1, Name1, Name2

Line Input # Statement

This function reads a single line from an open sequential file and assigns it to a string variable.

Line Input #filenumber, varname

For example:

Line Input #1, OneLine

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