InputBox Function

Displays a prompt in a dialog box, waits for the user to input text or click a button, and returns a String containing the contents of the text box.

Syntax

InputBox(prompt[, title][, default][, xpos][, ypos][, helpfile, context])

Parameters

prompt (Required): String expression displayed as the message in the dialog box. Maximum length is approximately 1024 characters, depending on width of characters used. Can include line breaks using vbCrLf, vbNewLine, or Chr(13) & Chr(10)
title (Optional): String expression displayed in the title bar of the dialog box. If omitted, the application name is displayed
default (Optional): String expression displayed in the text box as the default response if no other input is provided. If omitted, the text box is displayed empty
xpos (Optional): Numeric expression that specifies, in twips, the horizontal distance from the left edge of the screen. If omitted, the dialog box is horizontally centered
ypos (Optional): Numeric expression that specifies, in twips, the vertical distance from the top of the screen. If omitted, the dialog box is positioned vertically approximately one-third down the screen
helpfile (Optional): String expression that identifies the Help file to use. If provided, context must also be provided
context (Optional): Numeric expression that identifies the Help context number assigned to the Help topic. If provided, helpfile must also be provided

Return Value

Returns a String: - If OK is clicked or Enter is pressed: Returns the text in the text box - If Cancel is clicked: Returns an empty string ("") - If Esc is pressed: Returns an empty string ("") - If the default parameter is provided and user clicks OK without entering text: Returns the default value

Remarks

The InputBox function provides a simple way to get user input: - Displays a modal dialog box that blocks execution until user responds - The dialog always includes OK and Cancel buttons - Pressing Enter is equivalent to clicking OK - Pressing Esc is equivalent to clicking Cancel - Cannot distinguish between Cancel and an empty string entered by user - For multi-line input, use a custom form instead - Maximum prompt length is approximately 1024 characters - Position parameters (xpos, ypos) are in twips (1440 twips = 1 inch) - Help integration requires both helpfile and context parameters - The text box accepts a single line of text (no multi-line support) - Input is returned as typed (no automatic validation or conversion) - Always returns a String, even if numeric input is expected

Typical Uses

Simple User Input: Get basic text input from users
Configuration Values: Prompt for settings or preferences
Data Entry: Quick single-value data entry
File Names: Prompt for file or folder names
Search Terms: Get search queries from users
Passwords: Simple password entry (though text is visible)
Numeric Input: Get numeric values (requires validation)
Confirmation Input: Request verification text from users

Basic Usage Examples

' Example 1: Simple input
Dim userName As String
userName = InputBox("Enter your name:")
If userName <> "" Then
    MsgBox "Hello, " & userName
End If
' Example 2: With title and default
Dim age As String
age = InputBox("Enter your age:", "Age Entry", "18")
If IsNumeric(age) Then
    MsgBox "You are " & age & " years old"
End If
' Example 3: With position
Dim response As String
response = InputBox("Enter response:", "Input", "", 1000, 1000)
' Example 4: Multi-line prompt
Dim email As String
email = InputBox("Please enter your email address:" & vbCrLf & _
                 "This will be used for notifications.", _
                 "Email Address")

Common Patterns

' Pattern 1: Validate numeric input
Function GetNumericInput(prompt As String, Optional default As String = "0") As Double
    Dim input As String
    Dim result As Double
    Do
        input = InputBox(prompt, "Numeric Input", default)
        If input = "" Then
            GetNumericInput = 0
            Exit Function
        End If
        If IsNumeric(input) Then
            GetNumericInput = CDbl(input)
            Exit Function
        End If
        MsgBox "Please enter a valid number", vbExclamation
    Loop
End Function
' Pattern 2: Required input (loop until provided)
Function GetRequiredInput(prompt As String, title As String) As String
    Dim input As String
    Do
        input = InputBox(prompt, title)
        If input <> "" Then
            GetRequiredInput = input
            Exit Function
        End If
        If MsgBox("Input is required. Try again?", vbYesNo) = vbNo Then
            GetRequiredInput = ""
            Exit Function
        End If
    Loop
End Function
' Pattern 3: Input with validation
Function GetEmailAddress() As String
    Dim email As String
    Do
        email = InputBox("Enter your email address:", "Email")
        If email = "" Then
            GetEmailAddress = ""
            Exit Function
        End If
        If InStr(email, "@") > 0 And InStr(email, ".") > 0 Then
            GetEmailAddress = email
            Exit Function
        End If
        MsgBox "Please enter a valid email address", vbExclamation
    Loop
End Function
' Pattern 4: Input with range validation
Function GetIntegerInRange(prompt As String, minVal As Long, maxVal As Long) As Long
    Dim input As String
    Dim value As Long
    Do
        input = InputBox(prompt & vbCrLf & _
                        "Range: " & minVal & " to " & maxVal, _
                        "Input", CStr(minVal))
        If input = "" Then
            GetIntegerInRange = minVal
            Exit Function
        End If
        If IsNumeric(input) Then
            value = CLng(input)
            If value >= minVal And value <= maxVal Then
                GetIntegerInRange = value
                Exit Function
            End If
        End If
        MsgBox "Please enter a value between " & minVal & " and " & maxVal, vbExclamation
    Loop
End Function
' Pattern 5: File name input with validation
Function GetFileName(prompt As String, Optional extension As String = "") As String
    Dim fileName As String
    Do
        fileName = InputBox(prompt, "File Name")
        If fileName = "" Then
            GetFileName = ""
            Exit Function
        End If
        ' Check for invalid characters
        If InStr(fileName, "\") > 0 Or InStr(fileName, "/") > 0 Or _
           InStr(fileName, ":") > 0 Or InStr(fileName, "*") > 0 Or _
           InStr(fileName, "?") > 0 Or InStr(fileName, """") > 0 Or _
           InStr(fileName, "<") > 0 Or InStr(fileName, ">") > 0 Or _
           InStr(fileName, "|") > 0 Then
            MsgBox "File name contains invalid characters", vbExclamation
        Else
            If extension <> "" And Right$(fileName, Len(extension)) <> extension Then
                fileName = fileName & extension
            End If
            GetFileName = fileName
            Exit Function
        End If
    Loop
End Function
' Pattern 6: Password input (simple - visible text)
Function GetPassword(prompt As String) As String
    Dim password As String
    Dim confirm As String
    password = InputBox(prompt, "Password")
    If password = "" Then
        GetPassword = ""
        Exit Function
    End If
    confirm = InputBox("Confirm password:", "Confirm Password")
    If password = confirm Then
        GetPassword = password
    Else
        MsgBox "Passwords do not match", vbExclamation
        GetPassword = ""
    End If
End Function
' Pattern 7: Multiple inputs in sequence
Sub GetUserInfo()
    Dim firstName As String
    Dim lastName As String
    Dim email As String
    firstName = InputBox("Enter first name:", "User Information")
    If firstName = "" Then Exit Sub
    lastName = InputBox("Enter last name:", "User Information")
    If lastName = "" Then Exit Sub
    email = InputBox("Enter email:", "User Information")
    If email = "" Then Exit Sub
    MsgBox "User: " & firstName & " " & lastName & vbCrLf & _
           "Email: " & email
End Sub
' Pattern 8: Input with list of options in prompt
Function GetOption() As String
    Dim choice As String
    Dim prompt As String
    prompt = "Select an option:" & vbCrLf & _
             "1 - Create new file" & vbCrLf & _
             "2 - Open existing file" & vbCrLf & _
             "3 - Exit" & vbCrLf & vbCrLf & _
             "Enter choice (1-3):"
    choice = InputBox(prompt, "Main Menu", "1")
    Select Case choice
        Case "1", "2", "3"
            GetOption = choice
        Case Else
            GetOption = ""
    End Select
End Function
' Pattern 9: Trim and clean input
Function GetCleanInput(prompt As String, title As String) As String
    Dim input As String
    input = InputBox(prompt, title)
    ' Trim whitespace
    input = Trim$(input)
    ' Remove multiple spaces
    Do While InStr(input, "  ") > 0
        input = Replace(input, "  ", " ")
    Loop
    GetCleanInput = input
End Function
' Pattern 10: Cancel detection with default
Function GetInputWithCancelDetection(prompt As String, defaultValue As String) As Variant
    Dim input As String
    input = InputBox(prompt, "Input", defaultValue)
    If input = "" And defaultValue <> "" Then
        ' User likely clicked Cancel
        GetInputWithCancelDetection = Null
    Else
        GetInputWithCancelDetection = input
    End If
End Function

Advanced Usage Examples

' Example 1: Configuration manager with InputBox
Public Class ConfigManager
    Private m_settings As Collection
    Private Sub Class_Initialize()
        Set m_settings = New Collection
    End Sub
    Public Function GetSetting(key As String, prompt As String, _
                               Optional defaultValue As String = "") As String
        On Error Resume Next
        GetSetting = m_settings(key)
        If Err.Number <> 0 Or GetSetting = "" Then
            Err.Clear
            GetSetting = InputBox(prompt, "Configuration: " & key, defaultValue)
            If GetSetting <> "" Then
                m_settings.Add GetSetting, key
            End If
        End If
        On Error GoTo 0
    End Function
    Public Sub ClearSettings()
        Set m_settings = New Collection
    End Sub
End Class
' Example 2: Data validation wrapper
Public Class InputValidator
    Public Enum ValidationType
        vtText = 0
        vtInteger = 1
        vtDecimal = 2
        vtEmail = 3
        vtDate = 4
    End Enum
    Public Function GetValidatedInput(prompt As String, _
                                      validationType As ValidationType, _
                                      Optional title As String = "Input", _
                                      Optional defaultValue As String = "") As Variant
        Dim input As String
        Dim isValid As Boolean
        Do
            input = InputBox(prompt, title, defaultValue)
            If input = "" Then
                GetValidatedInput = Null
                Exit Function
            End If
            isValid = ValidateInput(input, validationType)
            If isValid Then
                GetValidatedInput = ConvertInput(input, validationType)
                Exit Function
            Else
                MsgBox "Invalid input. Please try again.", vbExclamation
            End If
        Loop
    End Function
    Private Function ValidateInput(input As String, vType As ValidationType) As Boolean
        Select Case vType
            Case vtText
                ValidateInput = Len(input) > 0
            Case vtInteger
                ValidateInput = IsNumeric(input) And InStr(input, ".") = 0
            Case vtDecimal
                ValidateInput = IsNumeric(input)
            Case vtEmail
                ValidateInput = InStr(input, "@") > 0 And InStr(input, ".") > 0
            Case vtDate
                ValidateInput = IsDate(input)
            Case Else
                ValidateInput = False
        End Select
    End Function
    Private Function ConvertInput(input As String, vType As ValidationType) As Variant
        Select Case vType
            Case vtInteger
                ConvertInput = CLng(input)
            Case vtDecimal
                ConvertInput = CDbl(input)
            Case vtDate
                ConvertInput = CDate(input)
            Case Else
                ConvertInput = input
        End Select
    End Function
End Class
' Example 3: Wizard-style input sequence
Function RunWizard() As Boolean
    Dim step1 As String, step2 As String, step3 As String
    Dim prompt As String
    ' Step 1
    prompt = "Step 1 of 3:" & vbCrLf & _
             "Enter project name:"
    step1 = InputBox(prompt, "Project Wizard")
    If step1 = "" Then
        RunWizard = False
        Exit Function
    End If
    ' Step 2
    prompt = "Step 2 of 3:" & vbCrLf & _
             "Enter project location:"
    step2 = InputBox(prompt, "Project Wizard", "C:\Projects")
    If step2 = "" Then
        RunWizard = False
        Exit Function
    End If
    ' Step 3
    prompt = "Step 3 of 3:" & vbCrLf & _
             "Enter description:"
    step3 = InputBox(prompt, "Project Wizard")
    If step3 = "" Then step3 = "(No description)"
    ' Create project
    MsgBox "Creating project:" & vbCrLf & _
           "Name: " & step1 & vbCrLf & _
           "Location: " & step2 & vbCrLf & _
           "Description: " & step3
    RunWizard = True
End Function
' Example 4: Search query builder
Function BuildSearchQuery() As String
    Dim searchTerm As String
    Dim filters As String
    Dim query As String
    searchTerm = InputBox("Enter search term:", "Search")
    If searchTerm = "" Then
        BuildSearchQuery = ""
        Exit Function
    End If
    filters = InputBox("Enter filters (optional):" & vbCrLf & _
                      "Examples: category:books, year:2020", _
                      "Search Filters")
    query = "search=" & searchTerm
    If filters <> "" Then
        query = query & "&filters=" & filters
    End If
    BuildSearchQuery = query
End Function

Error Handling

The InputBox function rarely raises errors, but should be used with error handling:

On Error GoTo ErrorHandler
Dim userInput As String
userInput = InputBox("Enter value:", "Input")
If userInput = "" Then
    MsgBox "No input provided", vbInformation
Else
    ProcessInput userInput
End If
Exit Sub
ErrorHandler:
    MsgBox "Error getting input: " & Err.Description, vbCritical

Performance Considerations

Modal Dialog: Blocks execution until user responds
User Interaction: Performance depends entirely on user response time
String Returns: Always returns a String regardless of expected data type
No Timeout: Dialog waits indefinitely for user action
Lightweight: Minimal overhead for displaying dialog

Best Practices

Clear Prompts: Write clear, concise prompts that explain what input is needed
Validate Input: Always validate and convert input as needed (InputBox returns String)
Handle Cancel: Check for empty string return value (could be Cancel or empty input)
Provide Defaults: Use default parameter for common or suggested values
Error Handling: Wrap InputBox calls in error handling
Alternative UI: For complex input, use custom forms instead of InputBox
Accessibility: Consider users who need keyboard navigation
Multi-line Prompts: Use vbCrLf to create multi-line prompts for clarity

Comparison with Other Functions

Function	Purpose	Return Type
`InputBox`	Get user text input	`String`
`MsgBox`	Display message, get button click	`VbMsgBoxResult`
Custom Form	Complex input with multiple fields	Varies
`FileDialog`	Get file/folder selection	`String`

Platform and Version Notes

Available in all VB6 versions
Dialog appearance follows Windows theme
Maximum prompt length is approximately 1024 characters
Position parameters use twips (1440 twips = 1 inch)
No built-in password masking (text is visible)
Help integration requires compiled help files (.hlp or .chm)

Limitations

Single-line text input only (no multi-line support)
Cannot distinguish between Cancel and empty input
No input masking for passwords
No built-in validation
Modal dialog blocks all application interaction
No timeout option (waits indefinitely)
Limited formatting options for prompt text
Cannot customize button labels (always OK/Cancel)
No progress indication for long operations

MsgBox: Display messages and get button responses
Input: Read from files (different from InputBox)
Custom Forms: For complex input scenarios
Shell: Execute external programs for advanced input