String includin Escape character

问题

In textfield when user enter value with escape character, I want to work this same as user enter but it behaves like a string for \e too.

In more detail. suppose user have entered \e[3~ but when i print it in console it shows \e[3~. Actually this should print like ¿[3~ so it will work perfect for me.

I have tried by this line and it works.

NSString * str=[textField.text stringByReplacingOccurrencesOfString:@"\\e" withString:@"\e"];

But suppose if user enter value in caps like \E[3~ then its not replacing. so i have tried with like

NSString * str=[textField.text stringByReplacingOccurrencesOfString:@"\\e" withString:@"\e"];
        str=[textField.text stringByReplacingOccurrencesOfString:@"\\E" withString:@"\E"];

But this is not working in case while user have entered text in small \e[3~. With this when first line will execute to replace \e it will give me perfect result like ¿[3~ but when it will execute next line it gives me same \e[3~ string.

Please suggest me how can i check for both letters and if i can check for all escaping characters at once.

回答1:

The error in your code is that the second line takes the original string textField.text instead of the result from the first line. What you probably meant is:

NSString *str = [textField.text stringByReplacingOccurrencesOfString:@"\\e" withString:@"\e"];
str = [str stringByReplacingOccurrencesOfString:@"\\E" withString:@"\E"];

Alternatively, you can do the replacement in a single step by using the NSCaseInsensitiveSearch option:

NSString *str = [textField.text stringByReplacingOccurrencesOfString:@"\\e"
                        withString:@"\e"
                           options:NSCaseInsensitiveSearch
                             range:NSMakeRange(0, [textField.text length])];

来源：https://stackoverflow.com/questions/19629634/string-includin-escape-character

标签

iphone

unicode

escaping