How Can I Pass a String Value from a Child Form to a Parent Form?
Pass data between parent form and child form
Many programming scenarios require exchanging data between parent and child forms. For example, a subform displays the user interface, and you need to retrieve a value from the subform and use it in the parent form.
How to return a string value to the parent form?
To pass values from a child form back to the parent form, follow these steps:
-
Define a property or method in the subform: Create a property or method in the subform to retrieve the value to be passed back. In this case, you need to pass a string. For example, you can create an attribute called
GetValue()
. -
Open the subform: Use the
new
keyword to instantiate the subform and specify the parent form in the constructor, for example:using (FormOptions formOptions = new FormOptions(this)) { // 使用 formOptions 的逻辑 }
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Update subform: In the subform, update a property or method with the value you want to return.
-
Retrieve the value in the parent form: After closing the child form, you can access the value by calling a property or method on the child form instance, for example:
string result = formOptions.GetValue();
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Here is a code example:
// 子窗体 (FormOptions) 中的代码 private string _myResult; public string GetMyResult { get { return _myResult; } set { _myResult = value; } } // 父窗体中的代码 using (FormOptions formOptions = new FormOptions(this)) { formOptions.ShowDialog(); string result = formOptions.GetMyResult; // 使用 result ... }
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