ios 如何在 UITextView 中检测用户输入字符
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How to detect user input character in UITextView
提问by Jason Zhao
How to detect user input character in UITextView?
如何在 UITextView 中检测用户输入字符？
For example:(in UITextView NOT UITextField)
例如：（在 UITextView NOT UITextField 中）
when user input letter "a", trigger an event. when user input "do it", trigger another event. or input "http://www.stackoverflow.com" trigger an event.
当用户输入字母“a”时，触发一个事件。当用户输入“do it”时，触发另一个事件。或输入“http://www.stackoverflow.com”触发事件。
Thanks
谢谢
采纳答案by Kuldeep
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
NSString * length;
NSString *currentString = [textField.text stringByReplacingCharactersInRange:range withString:string];
length = [currentString length];
if (length > 1)
{
looprange = _looptext.text;
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Please ! "
message:@"Insert Single Characters !!"
delegate:self
cancelButtonTitle:@"OK"
otherButtonTitles:nil];
[alert show];
return NO;
}
}
回答by Selvin
You can monitor the TextView content changes inside this delegate method and trigger necessary actions.
您可以监视此委托方法内的 TextView 内容更改并触发必要的操作。
- (void)textViewDidChange:(UITextView *)textView
{
//Access the textView Content
//From here you can get the last text entered by the user
NSArray *stringsSeparatedBySpace = [textView.text componentsSeparatedByString:@" "];
//then you can check whether its one of your userstrings and trigger the event
NSString *lastString = [stringsSeparatedBySpace lastObject];
if([lastString isEqualToString:@"http://www.stackoverflow.com"]) //add more conditions here
{
[self callActionMethod];
}
}
回答by iPrabu
This delegate will be called whenever a user presses key
每当用户按下键时都会调用此委托
Try this :-
尝试这个 ：-
- (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text
{
if([[textView.text stringByAppendingString:text] isEqualToString:@"a"])
{
//trigger 'a' operation
}
else if([[textView.text stringByAppendingString:text] isEqualToString:@"do it"])
{
//trigger do it operation
}
//Same conditions go on
}
回答by Devbot10
Working Swift 3 Solution
工作 Swift 3 解决方案
First, add UITextViewDelegate
首先，添加 UITextViewDelegate
Then, set delegate in viewDidLoadlike so, self.testTextField.delegate = self
然后，viewDidLoad像这样设置委托，self.testTextField.delegate = self
And finally, call the function textViewDidChange, example below.
最后，调用函数textViewDidChange，示例如下。
func textViewDidChange(_ textView: UITextView) {
// Do the logic you want to happen everytime the textView changes
// if string is == "do it" etc....
}
