Class SfNumericTextBox<TValue>

The NumericTextBox is used to get the number inputs from the user. The input values can be incremented or decremented by a predefined step value.

Inheritance
System.Object
SfBaseComponent
SfInputTextBase<TValue>
SfNumericTextBox<TValue>
Inherited Members
Syncfusion.Blazor.Inputs.SfInputTextBase<TValue>.BlurHandler(System.String, System.Boolean)
Syncfusion.Blazor.Inputs.SfInputTextBase<TValue>.ClickStopPropagation
Syncfusion.Blazor.Inputs.SfInputTextBase<TValue>.ContainerClass
Syncfusion.Blazor.Inputs.SfInputTextBase<TValue>.IsValueTemplate
Syncfusion.Blazor.Inputs.SfInputTextBase<TValue>.MouseDowSpinnerPrevent
Syncfusion.Blazor.Inputs.SfInputTextBase<TValue>.MousePreventContainer
Syncfusion.Blazor.Inputs.SfInputTextBase<TValue>.OnBlur
Syncfusion.Blazor.Inputs.SfInputTextBase<TValue>.OnChange
Syncfusion.Blazor.Inputs.SfInputTextBase<TValue>.OnFocus
Syncfusion.Blazor.Inputs.SfInputTextBase<TValue>.OnInput
Syncfusion.Blazor.Inputs.SfInputTextBase<TValue>.OnPaste
Syncfusion.Blazor.Inputs.SfInputTextBase<TValue>.PreventIconHandler
Syncfusion.Blazor.Inputs.SfInputTextBase<TValue>.RootClass
Syncfusion.Blazor.Inputs.SfInputTextBase<TValue>.SpinButton
Syncfusion.Blazor.Inputs.SfInputTextBase<TValue>.ValueExpression
Syncfusion.Blazor.Inputs.SfInputTextBase<TValue>.ValueTemplate
Namespace: Syncfusion.Blazor.Inputs
Assembly: Syncfusion.Blazor.dll
Syntax
public class SfNumericTextBox<TValue> : SfInputTextBase<TValue>
Type Parameters
Name Description
TValue

Specifies the generic type of the SfNumericTextBox<TValue> component. This type determines the data type of the numeric value that can be entered and processed by the component.
Remarks

The SfNumericTextBox<TValue> component provides a user-friendly interface for numeric input with features like spin buttons, validation, formatting, and culture-specific number display. It supports various numeric types including int, double, decimal, float, and their nullable counterparts.

Examples

A simple NumericTextBox component.

<SfNumericTextBox TValue="int" Value="10" Min="0" Max="100" Step="1"></SfNumericTextBox>

Constructors

SfNumericTextBox()

Declaration
public SfNumericTextBox()

Properties

BaseFloatLabelType

Declaration
protected override FloatLabelType BaseFloatLabelType { get; set; }
Property Value
Type
FloatLabelType
Overrides
Syncfusion.Blazor.Inputs.SfInputTextBase<TValue>.BaseFloatLabelType

BaseHtmlAttributes

Declaration
protected override Dictionary<string, object> BaseHtmlAttributes { get; set; }
Property Value
Type
System.Collections.Generic.Dictionary<System.String, System.Object>
Overrides
Syncfusion.Blazor.Inputs.SfInputTextBase<TValue>.BaseHtmlAttributes

BaseInputAttributes

Declaration
protected override Dictionary<string, object> BaseInputAttributes { get; set; }
Property Value
Type
System.Collections.Generic.Dictionary<System.String, System.Object>
Overrides
Syncfusion.Blazor.Inputs.SfInputTextBase<TValue>.BaseInputAttributes

BaseIsReadOnlyInput

Declaration
protected override bool BaseIsReadOnlyInput { get; set; }
Property Value
Type
System.Boolean
Overrides
Syncfusion.Blazor.Inputs.SfInputTextBase<TValue>.BaseIsReadOnlyInput

BasePlaceholder

Declaration
protected override string BasePlaceholder { get; set; }
Property Value
Type
System.String
Overrides
Syncfusion.Blazor.Inputs.SfInputTextBase<TValue>.BasePlaceholder

BaseReadonly

Declaration
protected override bool BaseReadonly { get; set; }
Property Value
Type
System.Boolean
Overrides
Syncfusion.Blazor.Inputs.SfInputTextBase<TValue>.BaseReadonly

BaseShowClearButton

Declaration
protected override bool BaseShowClearButton { get; set; }
Property Value
Type
System.Boolean
Overrides
Syncfusion.Blazor.Inputs.SfInputTextBase<TValue>.BaseShowClearButton

BaseTabIndex

Declaration
protected override int BaseTabIndex { get; set; }
Property Value
Type
System.Int32
Overrides
Syncfusion.Blazor.Inputs.SfInputTextBase<TValue>.BaseTabIndex

BaseWidth

Declaration
protected override string BaseWidth { get; set; }
Property Value
Type
System.String
Overrides
Syncfusion.Blazor.Inputs.SfInputTextBase<TValue>.BaseWidth

Currency

Gets or sets the currency code to use in currency formatting. Possible values are the ISO 4217 currency codes, such as USD for the US dollar and EUR for the euro.

Declaration
public string Currency { get; set; }
Property Value
Type Description
System.String

A string value representing the ISO 4217 currency code. The default value is null.
Remarks

This property enables currency formatting for the numeric values displayed in the SfNumericTextBox<TValue>. When set, the component will format numbers according to the specified currency's conventions. Common examples include "USD" for US Dollar, "EUR" for Euro, "GBP" for British Pound, etc.

Examples
<SfNumericTextBox TValue="decimal?" Currency="USD" Placeholder="Enter amount">
</SfNumericTextBox>

Decimals

Gets or sets the number of decimal places to display for numeric values.

Declaration
public Nullable<int> Decimals { get; set; }
Property Value
Type Description
System.Nullable<System.Int32>

An integer value representing the number of decimal places. Use null to display the default number of decimal places. The default value is null.
Remarks

This property controls the precision of decimal values displayed in the SfNumericTextBox<TValue>. When set to a specific value, the component will format numbers to show exactly that many decimal places. If set to null, the component will use the default decimal precision based on the data type and format string.

Examples
<SfNumericTextBox TValue="decimal?" Decimals="3" Placeholder="Enter value">
</SfNumericTextBox>

FloatLabelType

Gets or sets the floating label behavior of the SfNumericTextBox<TValue>. The Placeholder text act as a lable.

Declaration
public FloatLabelType FloatLabelType { get; set; }
Property Value
Type Description
FloatLabelType

One of the FloatLabelType enumeration. The default value is Never
Remarks

If the FloatLabelType is Never, the placeholder text does not float as a label. If the FloatLabelType is Auto, the placeholder text will float above the Numeric TextBox component as a label after focusing it. If the FloatLabelType is Always, the placeholder text is displayed as a label above the Numeric TextBox component.

Examples

In the following code example, set the float lable as Auto.

  <SfNumericTextBox TValue="int?" Placeholder="Enter the value" FloatLabelType="FloatLabelType.Auto">
  </SfNumericTextBox>

Format

Gets or sets the format string used to display numeric values.

Declaration
public string Format { get; set; }
Property Value
Type Description
System.String

A string value representing the format pattern. The default value is n2 which represents a number with two decimal places.
Remarks

You can customize the format string according to your requirements. The format string follows the standard format specifiers used in .NET formatting. For example, n3 would display a number with three decimal places.

Examples
  <SfNumericTextBox TValue="decimal?" Placeholder="Enter the value" Format="n3" >
  </SfNumericTextBox>

HtmlAttributes

Gets or sets a collection of additional attributes such as styles, class, and more that will be applied to the SfNumericTextBox<TValue> component.

Declaration
public Dictionary<string, object> HtmlAttributes { get; set; }
Property Value
Type Description
System.Collections.Generic.Dictionary<System.String, System.Object>

The value as dictionary collection.The default value is null
Remarks

If you configured both property and equivalent html attributes, then the component considers the property value.

Examples
<SfNumericTextBox TValue="int?" HtmlAttributes="@CustomAttribute">
</SfNumericTextBox>
@code{
    Dictionary<string, object> CustomAttribute = new Dictionary<string, object>()
    {
        { "title", "Please enter the unit" }
    };
}

InputAttributes

Gets or sets a collection of additional inputs attributes such as disabled, value, and more that will be applied to the TextBox component.

Declaration
public Dictionary<string, object> InputAttributes { get; set; }
Property Value
Type Description
System.Collections.Generic.Dictionary<System.String, System.Object>

The value as dictionary collection.The default value is null
Remarks

Additional attributes can be added by specifying as inline attributes or by specifying @attributes directive. If you configured both property and equivalent html attributes, then the component considers the property value.

Examples
<SfNumericTextBox TValue="int?" Placeholder="Enter the PIN" @attributes="@CustomAttribute">
</SfNumericTextBox>
@code{
    Dictionary<string, object> CustomAttribute = new Dictionary<string, object>()
    {
        { "maxlength", "4" }
    };
}

Max

Gets or sets the maximum allowable value for the input.

Declaration
public TValue Max { get; set; }
Property Value
Type Description
TValue

The maximum allowable value for the input. The default value is determined by the maximum possible value for the data type.
Remarks

This property defines the upper boundary for values that can be entered in the SfNumericTextBox<TValue>. When StrictMode is enabled, values exceeding this maximum will be automatically corrected to this maximum value. When StrictMode is disabled, values can exceed this maximum but will be flagged with an error state. The spin buttons and keyboard interactions respect this maximum limit.

Examples
<SfNumericTextBox TValue="int?" Placeholder="Enter the value" Max="10">
</SfNumericTextBox>

Min

Gets or sets the minimum allowable value for the input.

Declaration
public TValue Min { get; set; }
Property Value
Type Description
TValue

The minimum allowable value for the input. The default value is determined by the minimum possible value for the data type.
Remarks

This property defines the lower boundary for values that can be entered in the SfNumericTextBox<TValue>. When StrictMode is enabled, values below this minimum will be automatically corrected to this minimum value. When StrictMode is disabled, values can go below this minimum but will be flagged with an error state. The spin buttons and keyboard interactions respect this minimum limit.

Examples
<SfNumericTextBox TValue="int?" Placeholder="Enter the value" Min="5">
</SfNumericTextBox>

Placeholder

Gets or sets the text that is displayed when the SfNumericTextBox<TValue> has no value and remove on the focus.

Declaration
public string Placeholder { get; set; }
Property Value
Type Description
System.String

The text that is displayed when the TextBox has no value. The default value is String.Empty.
Remarks

The property depends on the FloatLabelType property, The placeholder text acts as a label.

Readonly

Gets or sets the boolean value whether the SfNumericTextBox<TValue> allows the user to change the text.

Declaration
public bool Readonly { get; set; }
Property Value
Type Description
System.Boolean

true, if the TextBox component cannot be edited. Otherwise, false.

ShowClearButton

Get or sets a value that indicates whether the clear button is displayed in SfNumericTextBox<TValue> component.

Declaration
public bool ShowClearButton { get; set; }
Property Value
Type Description
System.Boolean

true, if the clear button should be shown. Otherwise, false.The default is false.

ShowSpinButton

Gets or sets a value indicating whether to display spin buttons for incrementing and decrementing the numeric value.

Declaration
public bool ShowSpinButton { get; set; }
Property Value
Type Description
System.Boolean

true if spin buttons should be shown; otherwise, false. The default value is true.
Remarks

When enabled, the SfNumericTextBox<TValue> displays up and down arrow buttons that allow users to increment or decrement the numeric value. The spin buttons provide an intuitive way for users to adjust values without typing, especially useful for precise value adjustments. The increment/decrement amount is controlled by the Step property.

Examples
<SfNumericTextBox TValue="int?" ShowSpinButton="true" Step="5">
</SfNumericTextBox>

Step

Gets or sets the increment or decrement value for changing the numeric value.

Declaration
public TValue Step { get; set; }
Property Value
Type Description
TValue

The step value that determines how much the numeric value changes when interacting with the component. The default value varies based on the data type.
Remarks

This property defines the amount by which the value increases or decreases when users interact with the spin buttons, use keyboard arrow keys, or scroll the mouse wheel. The step value should be appropriate for the expected range and precision of values in your application. For example, use smaller step values for decimal numbers requiring precision, and larger step values for whole numbers.

Examples
<SfNumericTextBox TValue="int?" Placeholder="Enter the value" Step="5">
</SfNumericTextBox>

StrictMode

Gets or sets a value indicating whether the component operates in strict mode for value validation.

Declaration
public bool StrictMode { get; set; }
Property Value
Type Description
System.Boolean

true if input values are restricted between the minimum and maximum range; otherwise, false. The default value is true.
Remarks

When StrictMode is enabled (true), the input value will be automatically constrained between the Min and Max values. If a user enters a value outside this range, it will be corrected to the nearest boundary value when the component loses focus. When disabled (false), the component allows any value, even if it falls outside the specified range. In this case, an error class is applied to highlight invalid values visually.

Examples
<SfNumericTextBox TValue="int?" Min="1" Max="100" StrictMode="true">
</SfNumericTextBox>

TabIndex

Gets or sets the tab order of the SfNumericTextBox<TValue> component.

Declaration
public int TabIndex { get; set; }
Property Value
Type Description
System.Int32

An integer value representing the tab index of the component.

ValidateDecimalOnType

Gets or sets a value indicating whether to perform decimal validation during typing.

Declaration
public bool ValidateDecimalOnType { get; set; }
Property Value
Type Description
System.Boolean

true if decimal validation should be performed during typing; otherwise, false. The default value is false.
Remarks

When enabled, this property validates decimal input in real-time as the user types, preventing invalid decimal characters from being entered. This provides immediate feedback and ensures that only valid decimal values can be typed into the SfNumericTextBox<TValue>. When disabled, validation occurs only when the component loses focus or when the value is programmatically set.

Examples
<SfNumericTextBox TValue="decimal?" ValidateDecimalOnType="true">
</SfNumericTextBox>

Width

Gets or sets the width of the SfNumericTextBox<TValue> component.

Declaration
public string Width { get; set; }
Property Value
Type Description
System.String

The preferred width in pixels or percentage value. The default value is 100%.
Examples
  <SfNumericTextBox TValue="int?" Width="200px">
  </SfNumericTextBox>

Methods

BuildRenderTree(RenderTreeBuilder)

Declaration
protected override void BuildRenderTree(RenderTreeBuilder __builder)
Parameters
Type Name Description
Microsoft.AspNetCore.Components.Rendering.RenderTreeBuilder __builder

ChangeHandler(ChangeEventArgs)

Handles the change event when the input value is modified by the user.

Declaration
protected override Task ChangeHandler(ChangeEventArgs args)
Parameters
Type Name Description
Microsoft.AspNetCore.Components.ChangeEventArgs args

The change event arguments containing the new input value.
Returns
Type Description
System.Threading.Tasks.Task

A System.Threading.Tasks.Task representing the asynchronous change handling operation.
Overrides
Syncfusion.Blazor.Inputs.SfInputTextBase<TValue>.ChangeHandler(Microsoft.AspNetCore.Components.ChangeEventArgs)
Remarks

This method is responsible for processing user input and performs the following operations:

  • Handles drag-and-drop input sanitization
  • Processes full-width character conversion
  • Validates numeric input against allowed patterns
  • Handles both double and decimal parsing based on data type
  • Applies strict mode constraints and formatting
  • Manages paste operations and invalid input states
The method supports culture-specific number formatting and ensures proper validation of numeric input.

DecrementAsync(TValue)

Decrements the value asynchronously by the specified step.

Declaration
public Task DecrementAsync(TValue step)
Parameters
Type Name Description
TValue step

The step value by which to decrement the current value. If not provided, the numeric value will be decremented based on the Step property value.
Returns
Type Description
System.Threading.Tasks.Task

A System.Threading.Tasks.Task representing the asynchronous operation.
Remarks

This method decreases the current value of the SfNumericTextBox<TValue> by the specified step amount. The operation is performed asynchronously and will trigger the change event after the value is updated. If the resulting value goes below the minimum allowed value, it will be constrained to the minimum value.

Examples
// Decrement by a custom step value
await numericTextBox.DecrementAsync(5);

// Decrement by the default step value
await numericTextBox.DecrementAsync(default(TValue));

FocusAsync()

Sets the focus to the NumericTextBox component for interaction.

Declaration
public Task FocusAsync()
Returns
Type Description
System.Threading.Tasks.Task

A System.Threading.Tasks.Task representing the asynchronous operation.
Remarks

This method programmatically focuses the SfNumericTextBox<TValue> component, making it ready for user input. When focused, the component will be highlighted and ready to receive keyboard input or other user interactions. This is useful for accessibility scenarios or when you need to direct user attention to the component.

Examples
// Focus the numeric textbox
await numericTextBox.FocusAsync();

FocusHandler(FocusEventArgs)

Handles the focus event when the numeric textbox receives focus.

Declaration
protected override Task FocusHandler(FocusEventArgs args)
Parameters
Type Name Description
Microsoft.AspNetCore.Components.Web.FocusEventArgs args

The focus event arguments containing event details.
Returns
Type Description
System.Threading.Tasks.Task

A System.Threading.Tasks.Task representing the asynchronous focus handling operation.
Overrides
Syncfusion.Blazor.Inputs.SfInputTextBase<TValue>.FocusHandler(Microsoft.AspNetCore.Components.Web.FocusEventArgs)
Remarks

This method is called when the input element receives focus. It triggers client-side focus handling only if the component is enabled, not readonly, and the focus handler hasn't been triggered yet. The focus handler manages input formatting and user interaction states.

FocusOutAsync()

Removes the focus from the NumericTextBox component, if the component is in focus state.

Declaration
public Task FocusOutAsync()
Returns
Type Description
System.Threading.Tasks.Task

A System.Threading.Tasks.Task representing the asynchronous operation.
Remarks

This method programmatically removes focus from the SfNumericTextBox<TValue> component. If the component is currently focused, it will lose focus and any pending input will be processed. This method is useful for form validation scenarios or when you need to blur the component programmatically.

Examples
// Remove focus from the numeric textbox
await numericTextBox.FocusOutAsync();

FocusOutHandler(FocusEventArgs)

Handles the blur event when the numeric textbox loses focus.

Declaration
protected override Task FocusOutHandler(FocusEventArgs args)
Parameters
Type Name Description
Microsoft.AspNetCore.Components.Web.FocusEventArgs args

The focus event arguments containing event details.
Returns
Type Description
System.Threading.Tasks.Task

A System.Threading.Tasks.Task representing the asynchronous blur handling operation.
Overrides
Syncfusion.Blazor.Inputs.SfInputTextBase<TValue>.FocusOutHandler(Microsoft.AspNetCore.Components.Web.FocusEventArgs)
Remarks

This method is called when the input element loses focus and performs the following operations:

  • Triggers the Blur event if subscribed
  • Validates and formats the current input value
  • Handles device-specific behavior for mobile platforms
  • Updates float label sizing
  • Parses and converts input text to appropriate numeric types
The method prevents recursive calls and ensures proper value conversion based on the data type (double or decimal).

FormatValue(String)

Converts a string input value to the appropriate numeric type based on the current component configuration.

Declaration
protected override TValue FormatValue(string genericValue)
Parameters
Type Name Description
System.String genericValue

The string value to be converted to the numeric type.
Returns
Type Description
TValue

The converted numeric value of type TValue, or default value if conversion fails.
Overrides
Syncfusion.Blazor.Inputs.SfInputTextBase<TValue>.FormatValue(System.String)
Remarks

This method handles culture-specific number parsing, decimal separator validation, and supports both double and decimal numeric types. It also manages formatting for focused input states and validates number formats.

Exceptions
Type Condition
System.Exception

Logs any unexpected errors that occur during value conversion to the console.

FormatValueAsString(TValue)

Formats the specified numeric value as a string representation based on the current formatting settings.

Declaration
protected override string FormatValueAsString(TValue formatValue)
Parameters
Type Name Description
TValue formatValue

The numeric value to be formatted.
Returns
Type Description
System.String

A string representation of the formatted value, or null if an error occurs.
Overrides
Syncfusion.Blazor.Inputs.SfInputTextBase<TValue>.FormatValueAsString(TValue)
Remarks

This method applies culture-specific formatting, handles exponential notation, manages decimal separators, and updates ARIA attributes for accessibility. The formatting behavior differs based on whether the input is focused or not.

Exceptions
Type Condition
System.Exception

Logs any unexpected errors that occur during formatting to the console.

GetFormattedText()

Gets the formatted text representation of the current value.

Declaration
public string GetFormattedText()
Returns
Type Description
System.String

A System.String containing the formatted text representation of the current value.
Remarks

This method returns the current value of the SfNumericTextBox<TValue> formatted according to the component's formatting settings. The formatting includes decimal places, currency symbols, percentage signs, and other culture-specific formatting as configured. This is useful when you need to display the formatted value in other parts of your application.

Examples
// Get the formatted text of the current value
string formattedText = numericTextBox.GetFormattedText();

GetPersistDataAsync()

Gets the properties to be maintained in the persisted state.

Declaration
public Task<string> GetPersistDataAsync()
Returns
Type Description
System.Threading.Tasks.Task<System.String>

A System.Threading.Tasks.Task<> representing the asynchronous operation. The task result contains a System.String with the persisted data.
Remarks

This method retrieves the persisted state data for the SfNumericTextBox<TValue> component from the browser's local storage. The persisted data includes component properties that should be maintained across page refreshes or application restarts. This is useful for maintaining user preferences and component state in web applications.

Examples
// Get persisted data
string persistedData = await numericTextBox.GetPersistDataAsync();

IncrementAsync(TValue)

Increments the NumericTextBox value with the specified step value.

Declaration
public Task IncrementAsync(TValue step)
Parameters
Type Name Description
TValue step

Specifies the value used to increment the NumericTextBox value. If not provided, the numeric value will be incremented based on the Step property value.
Returns
Type Description
System.Threading.Tasks.Task

A System.Threading.Tasks.Task representing the asynchronous operation.
Remarks

This method increases the current value of the SfNumericTextBox<TValue> by the specified step amount. The operation is performed asynchronously and will trigger the change event after the value is updated. If the resulting value exceeds the maximum allowed value, it will be constrained to the maximum value.

Examples
// Increment by a custom step value
await numericTextBox.IncrementAsync(10);

// Increment by the default step value
await numericTextBox.IncrementAsync(default(TValue));