QB64-PE/internal/help/LINE_INPUT.txt

The '''LINE INPUT''' statement requests a [[STRING]] keyboard entry from a program user.



{{PageSyntax}}
:: '''LINE INPUT''' [;] '''"'''[text prompt or question]'''"{,|;} string_variable$'''
:: '''LINE INPUT ; string_variable$'''


''[[Parameters]]:''
* [[semicolon]] after LINE INPUT stops the cursor after the entry and prevents screen roll on lowest two screen rows.
* ''text statement or question'' is optional, but quotes are necessary unless just a semicolon is used before the ''variable''.
* [[comma]] separator for a statement or [[semicolon]] for a question mark following the text. 
* No text with a semicolon displays a question mark with a space and keeps the cursor after the entry. 
* Requires ONE [[STRING|string]] variable to hold the entire text entry.


''Usage:'' 
* Cannot use numerical [[type]] variables or [[comma]] separated variable lists for multiple entries!
* Allows [[comma]]s and [[quotation mark]]s in the user input, unlike [[INPUT]] where commas denote extra input values and quotes delimit strings. 
* The statement stops the procedure until an entry is made. Pressing Enter ends the entry and code execution resumes.
* LINE INPUT does not trim off leading or trailing spaces in the string entry like [[INPUT]] string returns.
* Use [[VAL]] to convert string numbers and [[&O]](octal) or [[&H]](hexadecimal) prefixed entries into numerical values. 
* Use [[_DEST]] [[_CONSOLE]] before LINE INPUT statements to be used in a [[$CONSOLE|console]] window.
* '''Note: QB64''' will NOT remove CHR$(0) from the end of LINE INPUT string return values like Qbasic did.


''Example:'' Preventing screen roll after an input entry on the bottom 2 screen rows. 
{{CodeStart}} '' ''
{{Cl|SCREEN}} 12

{{Cl|COLOR}} 14: {{Cl|LOCATE}} 29, 2 '          place dursor at beginning of prompt liine
{{Cl|PRINT}} "Enter a name to search for... "; 'print prompt on screen
{{Cl|COLOR}} 15: {{Cl|LINE INPUT}} {{text|;|red}} "", name$ '       get search name from user
{{Cl|LOCATE}} 29, 2: {{Cl|PRINT}} {{Cl|SPC}}(78); '       erase previous prompt
n$ = {{Cl|UCASE$}}(name$) '                 convert search name to upper case
{{Cl|COLOR}} 14'                        change foreground color to yellow
{{Cl|LOCATE}} 29, 2: {{Cl|PRINT}} "Searching..."; 'print message
{{Cl|SLEEP}} 
{{CodeEnd}}
{{OutputStart}}{{text|Enter a name to search for...|#FFFF00}} █
{{OutputEnd}}
: ''Explanation:'' The {{text|red|red}} [[semicolon]] after LINE INPUT acts like a semicolon after a [[PRINT]], which keeps the print cursor on the same row.


''See also:'' 
* [[INPUT (file mode)]], [[INPUT (file statement)|INPUT #]], [[LINE INPUT (file statement)|LINE INPUT #]]
* [[INPUT]], [[INPUT$]] {{text|(keyboard input)}}
* [[COLOR]], [[LOCATE]] 
* [[INKEY$]]
* [[_KEYHIT]], [[_KEYDOWN]]


{{PageNavigation}}