代码如下：
static constNSInteger Max_Character_Num =4;
代码语言：javascript复制 - (IBAction)onTextFieldEditingChanged:(id)sender
{
NSString *lang = [[UITextInputMode currentInputMode] primaryLanguage];
if ([lang isEqualToString:@"zh-Hans"]) {
UITextRange *selectedRange = [self.tagNameTextField markedTextRange];
UITextPosition *position = [self.tagNameTextField positionFromPosition:selectedRange.start offset:0];
if (!position) {
if (self.tagNameTextField.text.length > Max_Character_Num) {
self.tagNameTextField.text = [self.tagNameTextField.text substringFrom:0 to:Max_Character_Num];
}
}
}else{
if (self.tagNameTextField.text.length > Max_Character_Num) {
self.tagNameTextField.text = [self.tagNameTextField.text substringFrom:0 to:Max_Character_Num];
}
}
} 
