Method wpfBuilder.Validation

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Overload

Sets a validation callback function for the last added element.

public wpfBuilder Validation(Func<FrameworkElement, string> func, Action<FrameworkElement> linkClick = null)

Parameters

func  (Func<FrameworkElement, string>) Function that returns an error string if element's value is invalid, else returns null.

linkClick  (Action<FrameworkElement>) If not null, called on error link click. For example can be used to make the element visible.

Returns

wpfBuilder

Remarks

The callback function will be called when clicked button OK or Apply or a button added with flag WBBFlags.Validate. If it returns a non-null string, the window stays open and button's click callback not called. The string is displayed in a tooltip.

Examples

var b = new wpfBuilder("Window").WinSize(300);
b.R.Add("Name", out TextBox tName)
	.Validation(o => string.IsNullOrWhiteSpace(tName.Text) ? "Name cannot be empty" : null);
b.R.Add("Count", out TextBox tCount)
	.Validation(o => int.TryParse(tCount.Text, out int i1) && i1 >= 0 && i1 <= 100 ? null : "Count must be 0-100");
b.R.AddOkCancel();
b.End();
if (!b.ShowDialog()) return;
print.it(tName.Text, tCount.Text.ToInt());