Implementing Syncfusion Windows Forms Integer TextBox

When to Use This Skill

Use this skill when you need to:

• Create numeric input fields that accept only integer values
• Set up value constraints (minimum and maximum bounds)
• Format and display numbers with custom separators
• Handle negative values and validation
• Respond to value changes and validation errors in Windows Forms applications
• Apply visual styling to numeric inputs (colors, borders)

Component Overview

The IntegerTextBox is a specialized Windows Forms control derived from the standard TextBox. It:

• Accepts and displays only integer data types
• Enforces min/max value constraints automatically
• Supports custom number formatting with group separators
• Provides events for value changes and validation errors
• Allows visual customization through colors and styling
• Handles null values and read-only states
• Supports leading zeros and negative value handling

Key Characteristics:

• Restricts input to integer values only
• Validates input in real-time
• Provides wrapper properties for null handling
• Offers formatting options without themes or localization
• Lightweight and responsive to user interactions

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Documentation & Navigation Guide

Choose the reference that matches your current task:

Getting Started

📄 Read: references/getting-started.md

• Installation and NuGet package setup
• Adding control through designer
• Adding control manually in C# code
• Setting minimum and maximum value constraints
• Initial configuration patterns

Visual Appearance

📄 Read: references/appearance.md

• Setting background colors
• Configuring text colors by value type (positive/negative/zero)
• Border styling
• Read-only state appearance
• Color reset methods

Data Handling & Formatting

📄 Read: references/data-formatting.md

• Number formatting options
• Group separators and group sizes
• Handling negative values and key inputs
• Leading zeros support
• Null value management
• Read-only with separate colors

Events & Interactions

📄 Read: references/events.md

• BindableValueChanged event usage
• IntegerValueChanged event handling
• ValidationError event patterns
• FormattedTextChanged and ClipTextChanged
• Event handler implementation examples

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Quick Start Example

Here's a minimal working example:

using Syncfusion.Windows.Forms.Tools;

// Add assembly reference: Syncfusion.Shared.Base
// Include namespace: Syncfusion.Windows.Forms.Tools

// Create and add control
IntegerTextBox integerTextBox1 = new IntegerTextBox();
this.Controls.Add(integerTextBox1);

// Set constraints
integerTextBox1.MaxValue = 999999;
integerTextBox1.MinValue = -999999;
integerTextBox1.IntegerValue = 0;

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Common Patterns

Pattern 1: Value-Based Color Coding

Display positive values in green, negative in red, zero in gray:

integerTextBox1.PositiveColor = System.Drawing.Color.Green;
integerTextBox1.NegativeColor = System.Drawing.Color.Red;
integerTextBox1.ZeroColor = System.Drawing.Color.Gray;

Pattern 2: Number Formatting with Separators

Format large numbers with custom separators (e.g., "1,234,567"):

integerTextBox1.NumberGroupSeparator = ",";
integerTextBox1.NumberGroupSizes = new int[] { 3 };
integerTextBox1.IntegerValue = 1234567;

Pattern 3: Handling Value Changes

Respond when the user enters a new value:

integerTextBox1.BindableValueChanged += 
    (sender, e) => MessageBox.Show($"New value: {integerTextBox1.IntegerValue}");

Pattern 4: Validation with Error Handling

Catch and respond to validation errors:

integerTextBox1.ValidationError += (sender, e) =>
{
    MessageBox.Show("Invalid input! Please enter a valid integer.");
};

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Key Properties

Property	Purpose	Example
MaxValue	Upper bound for integer values	integerTextBox1.MaxValue = 100;
MinValue	Lower bound for integer values	integerTextBox1.MinValue = 0;
IntegerValue	Get/set the current integer value	int val = integerTextBox1.IntegerValue;
BindableValue	Wrapper for null-safe value access	integerTextBox1.BindableValue = null;
AllowLeadingZeros	Allow zeros before number (e.g., "0123")	integerTextBox1.AllowLeadingZeros = true;
NumberGroupSeparator	Character to separate digit groups	integerTextBox1.NumberGroupSeparator = ",";
NumberGroupSizes	Size of each digit group	integerTextBox1.NumberGroupSizes = new int[] { 3 };
PositiveColor	Color for positive values	integerTextBox1.PositiveColor = Color.Green;
NegativeColor	Color for negative values	integerTextBox1.NegativeColor = Color.Red;
ZeroColor	Color when value is zero	integerTextBox1.ZeroColor = Color.Gray;
BackColor	Control background color	integerTextBox1.BackColor = Color.White;
ReadOnlyBackColor	Background when read-only	integerTextBox1.ReadOnlyBackColor = Color.LightGray;
ReadOnly	Prevent user editing	integerTextBox1.ReadOnly = true;
DeleteSelectionOnNegative	Delete selected text when minus pressed	integerTextBox1.DeleteSelectionOnNegative = true;

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Common Use Cases

Use Case 1: Financial Input with Constraints Create a textbox for dollar amounts (0 to 999,999):

integerTextBox1.MinValue = 0;
integerTextBox1.MaxValue = 999999;
integerTextBox1.NumberGroupSeparator = ",";
integerTextBox1.NumberGroupSizes = new int[] { 3 };

Use Case 2: Temperature Input (Negative & Positive) Allow temperatures from -50 to 50 degrees:

integerTextBox1.MinValue = -50;
integerTextBox1.MaxValue = 50;
integerTextBox1.NegativeColor = Color.Blue;
integerTextBox1.PositiveColor = Color.Red;

Use Case 3: Read-Only Display Show a value that users cannot modify:

integerTextBox1.IntegerValue = 42;
integerTextBox1.ReadOnly = true;
integerTextBox1.ReadOnlyBackColor = Color.LightGray;

Use Case 4: Null-Able Integer with Validation Allow null values with error handling:

integerTextBox1.BindableValueChanged += (sender, e) =>
{
    if (integerTextBox1.BindableValue == null)
        MessageBox.Show("Value cleared (null)");
    else
        MessageBox.Show($"Value: {integerTextBox1.IntegerValue}");
};

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Next Steps

• Start with Getting Started to install and create the control
• Customize appearance using Visual Appearance
• Handle data with Data Formatting
• Respond to user interactions with Events