onchange

问题 I'm using Formik for validation in a React app. Validation is working correctly, but my onChange handler does not fire: <Field type="text" name="name" placeholder="First Name" component={Input} onChange={() => console.log("gfdg")} /> Link to Sandbox Why is this? 回答1: Inside Input , the way you have ordered the props passed to your input element means your onChange is being overwritten by Formik's onChange . When you create a Field with a custom component (i.e. Input in your case), Formik

问题 My Excel project functions properly at home (with Excel 2010 ), but not on two work computers (with Excel 2016 ) and I suspect the Worksheet_Change event is the problem. When the user makes changes, the yellow bar (in the screenshot) should turn white again, but it is not. I am getting 2 different responses on 2 work computers. Two things to point out in the code: In some places I use vbColor extensions, in others I had to use a numerical code. One computer is not firing the Worksheet_Change

问题 In documentation for TComboBox = class(TCustomComboBox) there's this: property OnChange: TNotifyEvent; read write; , where TNotifyEvent = procedure(Sender: TObject); . Judging from that OnChange has no parameters, only the returned value. In Delphi OnChange event has the Sender: TObject parameter. Why is that allowed to type the following then and what does it mean if it's not the same as Sender: TObject ? WizardForm.TypesCombo.OnChange(WizardForm.TypesCombo) (taken from Inno Setup Remember

问题 We found this in our code (we haven't written it by our selfs, and we are new to programmng), can anyone explain what this.value means and how you change it? <select id="sel_target" onchange="paint(this.value);sendid(value); highlight(value);move_to(value)"> Thank you! 回答1: this.value represents the selected value. Example: function getComboA(sel) { var value = sel.value; } <select id="comboA" onchange="getComboA(this)"> <option value="">Select combo</option> <option value="Value1">Text1<

问题 We found this in our code (we haven't written it by our selfs, and we are new to programmng), can anyone explain what this.value means and how you change it? <select id="sel_target" onchange="paint(this.value);sendid(value); highlight(value);move_to(value)"> Thank you! 回答1: this.value represents the selected value. Example: function getComboA(sel) { var value = sel.value; } <select id="comboA" onchange="getComboA(this)"> <option value="">Select combo</option> <option value="Value1">Text1<

问题 I'm trying to refresh a Shuttle Item whenever a Select List item is modified. What I've done so far: I have an item P1_MY_LIST which is a list of value. And I have a P1_MY_SHUTTLE which is populated by this query : SELECT a, b FROM my_table WHERE col1 = :P1_MY_LIST; Then I created a Change event on P1_MY_LIST which contain a TRUE Event set to Refresh the P1_MY_SHUTTLE item. Yet, nothing happens when I select something in my P1_MY_LIST . Anyone knows what I'm doing wrong ? 回答1: For refreshing

问题 When I upload an image using react-image-uploader the onchange triggers twice. so it attempts to upload the image to the backend twice, here is how I handle it: //user uploads image to app <ImageUploader buttonClassName={"btn add-btn bg-orange"} buttonText='ADD' onChange={this.newProfilePicture} imgExtension={['.jpg', '.gif', '.png', '.gif']} maxFileSize={5242880} fileSizeError="file size is too big" fileTypeError="this file type is not supported" singleImage={true} withPreview={true} label={

问题 I know I must be missing something very simple but why is there no onChange for <Input> tag of Ant design ? I would like the update the value of an input. I assumed there was something like an onChange , since I was able to use onChange with DatePicker and handleChange DropDown ; but I guess I assumed wrong When I looked at the docs, there is a onPressEnter callback, but that is not really going to help me. I tried the following: <Input placeholder="Flight name" size="large" value={this.state

问题 //Assume am changing state in handleChange function. In case of onChange event state will update every character change. <input type="text" name="name" onChange={this.handleChange} id="name" /> In case of onBlur event state will update at single shot after leaving input fields. <input type="text" name="name" onBlur={this.handleChange} id="name" /> which approach is best to update the state in React and why ? 回答1: This is actually a trade-off decision. I assume that, in your event handler

问题 //Assume am changing state in handleChange function. In case of onChange event state will update every character change. <input type="text" name="name" onChange={this.handleChange} id="name" /> In case of onBlur event state will update at single shot after leaving input fields. <input type="text" name="name" onBlur={this.handleChange} id="name" /> which approach is best to update the state in React and why ? 回答1: This is actually a trade-off decision. I assume that, in your event handler