HTML数字输入框整数可预填充，小数无法显示问题求助

Hey there! Let's figure out why your pre-filled decimal value isn't showing up in the number input—integers working fine but decimals not is a classic sign of culture/formatting mismatch, especially since your label is in French (Temps prévu) which uses commas for decimal separators. Here are the most likely fixes:

1. Fix the Value Formatting with Invariant Culture #

The asp-for tag helper might be formatting the decimal value using your server's default culture (e.g., French, which uses , instead of .). Most browsers expect number inputs to use a dot (.) as the decimal separator by default, so they'll ignore values with commas entirely.

Add an explicit value attribute that formats the number with the invariant culture to force a dot separator:

<dd class="col-sm-9 detailsElements">
    <input asp-for="ExceptedTime" 
           class="form-control" 
           type="number" 
           step=".01" 
           required
           value="@Model.ExceptedTime.ToString(System.Globalization.CultureInfo.InvariantCulture)"/>
    <span asp-validation-for="ExceptedTime" class="text-danger"></span>
</dd>

This ensures the value is rendered as 2.4 instead of 2,4, which the browser's number input will recognize and display correctly.

2. Verify Your Model Field Type #

Double-check that your ExceptedTime property in the model is a decimal or double type, not an integer type like int or long. If it's an integer, the decimal value would get truncated before it even reaches the view:

// Correct type (supports decimals)
public decimal ExceptedTime { get; set; }

// Wrong type (truncates decimal values)
public int ExceptedTime { get; set; }

3. Test with a More Flexible Step Attribute #

While step=".01" is correct for two decimal places, some browsers can be picky about value precision matching the step. Try temporarily setting step="any" to see if the value displays—this disables strict step validation and lets any decimal value show up:

<input asp-for="ExceptedTime" class="form-control" type="number" step="any" required ... />

If this works, you can switch back to step=".01" once the formatting issue is fixed, since it's better for enforcing input precision.

4. Check Client-Side Validation Settings #

If you're using jQuery Validate (which ASP.NET Core uses by default for client validation), it might be enforcing culture-specific rules that conflict with the input's expected format. Add this script to your view or layout to make validation support both dot and comma separators:

$.validator.methods.number = function (value, element) {
    return this.optional(element) || /^-?(?:\d+|\d{1,3}(?:,\d{3})+)?(?:\.\d+)?$/.test(value);
};

内容的提问来源于stack exchange，提问作者VickeS