LINE INPUT: Difference between revisions

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(Created page with "The LINE INPUT statement requests a STRING keyboard entry from a program user. {{PageSyntax}} : LINE INPUT [;] "[text prompt or question]"{,|;} {{Parameter|stringVariable$}} : LINE INPUT ; {{Parameter|stringVariable$}} {{Parameters}} * A semicolon immediately after LINE INPUT stops the cursor after the entry and prevents screen roll on the lowest two screen rows. * ''text prompt or question'' is optional, but quotes are necessary unless just a sem...")
 
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{{Parameters}}
{{PageParameters}}
* A [[semicolon]] immediately after LINE INPUT stops the cursor after the entry and prevents screen roll on the lowest two screen rows.
* A [[semicolon]] immediately after LINE INPUT stops the cursor after the entry and prevents screen roll on the lowest two screen rows.
* ''text prompt or question'' is optional, but quotes are necessary unless just a semicolon is used before the {{Parameter|stringVariable$}}.
* ''text prompt or question'' is optional, but quotes are necessary unless just a semicolon is used before the {{Parameter|stringVariable$}}.
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{{PageDescription}}
{{PageDescription}}
* Cannot use numerical [[type]] variables or [[comma]] separated variable lists for multiple entries.
* Cannot use numerical [[Variable Types|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.  
* 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 halts the program until an entry is made. Pressing Enter ends the entry and code execution resumes.
* The statement halts the program 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.
* 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), [[&H]] (hexadecimal) or [[&B]] (binary) prefixed entries into numerical values.  
* Use [[VAL]] to convert string numbers and [[&O]] (octal), [[&H]] (hexadecimal) or [[&B]] (binary) prefixed entries into numerical values.
* Use [[_DEST]] [[_CONSOLE]] before LINE INPUT statements to receive input from a [[$CONSOLE|console]] window.
* Use [[_DEST]] [[_CONSOLE]] before LINE INPUT statements to receive input from a [[$CONSOLE|console]] window.
* '''Note: QB64''' will not remove CHR$(0) from the end of LINE INPUT string return values like QBasic did.
* '''Note: QB64''' will not remove CHR$(0) from the end of LINE INPUT string return values like QBasic did.
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{{PageExamples}}
{{PageExamples}}
''Example:'' Preventing screen roll after an input entry on the bottom 2 screen rows.  
''Example:'' Preventing screen roll after an input entry on the bottom 2 screen rows.
{{CodeStart}} '' ''
{{CodeStart}}
{{Cl|SCREEN}} 12
{{Cl|SCREEN}} 12


{{Cl|COLOR}} 14: {{Cl|LOCATE}} 29, 2 '          place dursor at beginning of prompt liine
{{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|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|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
{{Cl|LOCATE}} 29, 2: {{Cl|PRINT}} {{Cl|SPC}}(78); '      erase previous prompt
n$ = {{Cl|UCASE$}}(name$) '                convert search name to upper case
n$ = {{Cl|UCASE$}}(name$) '                convert search name to upper case
{{Cl|COLOR}} 14'                        change foreground color to yellow
{{Cl|COLOR}} 14'                        change foreground color to yellow
{{Cl|LOCATE}} 29, 2: {{Cl|PRINT}} "Searching..."; 'print message
{{Cl|LOCATE}} 29, 2: {{Cl|PRINT}} "Searching..."; 'print message
{{Cl|SLEEP}}  
{{Cl|SLEEP}}
{{CodeEnd}}
{{CodeEnd}}
{{OutputStart}}{{text|Enter a name to search for...|#FFFF00}} █
{{OutputStart}}
 
 
 
 
 
 
 
 
{{Text|Enter a name to search for...|#FFFF00}} █
{{OutputEnd}}
{{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.
: ''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:''
{{PageSeeAlso}}
* [[INPUT (file mode)]], [[INPUT (file statement)|INPUT #]], [[LINE INPUT (file statement)|LINE INPUT #]]
* [[INPUT (file mode)]], [[INPUT (file statement)|INPUT #]], [[LINE INPUT (file statement)|LINE INPUT #]]
* [[INPUT]], [[INPUT$]] {{text|(keyboard input)}}
* [[INPUT]], [[INPUT$]] {{Text|(keyboard input)}}
* [[COLOR]], [[LOCATE]]  
* [[COLOR]], [[LOCATE]]
* [[INKEY$]]
* [[INKEY$]]
* [[_KEYHIT]], [[_KEYDOWN]]
* [[_KEYHIT]], [[_KEYDOWN]]

Latest revision as of 20:25, 26 January 2024

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


Syntax

LINE INPUT [;] "[text prompt or question]"{,|;} stringVariable$
LINE INPUT ; stringVariable$


Parameters

  • A semicolon immediately after LINE INPUT stops the cursor after the entry and prevents screen roll on the lowest two screen rows.
  • text prompt or question is optional, but quotes are necessary unless just a semicolon is used before the stringVariable$.
  • Requires only one string variable to hold the entire text entry.


Description

  • Cannot use numerical type variables or comma separated variable lists for multiple entries.
  • Allows commas and quotation marks in the user input, unlike INPUT where commas denote extra input values and quotes delimit strings.
  • The statement halts the program 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), &H (hexadecimal) or &B (binary) prefixed entries into numerical values.
  • Use _DEST _CONSOLE before LINE INPUT statements to receive input from a console window.
  • Note: QB64 will not remove CHR$(0) from the end of LINE INPUT string return values like QBasic did.


Examples

Example: Preventing screen roll after an input entry on the bottom 2 screen rows. 

SCREEN 12

COLOR 14: LOCATE 29, 2 '          place dursor at beginning of prompt liine
PRINT "Enter a name to search for... "; 'print prompt on screen
COLOR 15: LINE INPUT ; "", name$ '       get search name from user
LOCATE 29, 2: PRINT SPC(78); '       erase previous prompt
n$ = UCASE$(name$) '                 convert search name to upper case
COLOR 14'                        change foreground color to yellow
LOCATE 29, 2: PRINT "Searching..."; 'print message
SLEEP









Enter a name to search for... █
Explanation: The red semicolon after LINE INPUT acts like a semicolon after a PRINT, which keeps the print cursor on the same row.


See also


Navigation:
Main Page with Articles and Tutorials
Keyword Reference - Alphabetical
Keyword Reference - By usage
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