added funtions, updated readme

README.md

@@ -7,6 +7,55 @@ Did you ever feel the need to manipulate a _string_ in C? Have you ever wanted t
 
 ---
 
+## Table of contents
+
+  * **[Setup](#setup)**
+  * **[Usage](#usage)**
+    - [strlen()](#getting-the-length-of-a-string)
+    - [strcpy()](#copying-a-string)
+    - [newstr()](#dynamically-creating-a-string)
+    - [strcat()](#concatenating-strings)
+    - [strequals()](#comparing-strings)
+    - _[Substrings](#creating-substrings)_
+      * [substr()](#creating-a-substring-to-the-end)
+      * [substring()](#creating-a-substring-from-...-to-...)
+    - _[Character indices](#getting-the-index-of-a-character)_
+      * [indexOf()](#first-index-of-character)
+      * [indexOfFrom()](#first-index-of-character-from-...)
+      * [lastIndexOf()](#last-index-of-character)
+    - _[Substring indices](#getting-the-index-of-a-substring)_
+      * [indexOfString()](#first-index-of-substring)
+      * [indexOfStringFrom()](#first-index-of-substring-from-...)
+      * [lastIndexOfString()](#last-index-of-substring)
+    - [charOccurrence()](#occurrence-of-a-character)
+    - [stringOccurrence()](#occurrence-of-a-substring)
+    - [split()](#split-at-character)
+    - [splits()](#split-at-substring)
+    - _[Lowercase](#convert-to-lowercase)_
+      * [lowerCase()](#lowercase-copy)
+      * [toLowerCase()](#value-to-lowercase)
+    - _[Uppercase](#convert-to-uppercase)_
+      * [upperCase()](#uppercase-copy)
+      * [toUpperCase()](#value-to-uppercase)
+    - [replace()](#replace-all-characters)
+    - [replaceString()](#replace-all-substrings)
+    - [trim()](#trim-whitespace)
+    - [itoc()](#integer-to-character)
+    - [ctoi()](#character-to-integer)
+    - _[To string](#convert-to-string)_
+      * [itos()](#integer-to-string)
+      * [btos()](#boolean-value-to-string)
+      * [ltos()](#long-to-string)
+      * [ftos()](#float-to-string)
+      * [dtos()](#double-to-string)
+    - _[From string](#convert-from-string)_
+      * [stoi()](#string-to-integer)
+      * [stob()](#string-to-boolean-value)
+      * [stol()](#string-to-long)
+      * [stof()](#string-to-float)
+      * [stod()](#string-to-double)
+  * **[Conclusion](#conclusion)**
+
 ## Setup
 
 To include the library in your project, you will need to import the `propaganda.h` header file.
@@ -131,7 +180,7 @@ You can create substrings in two different ways:
 
     ![exa5_output](media/05.JPG)
 
-  * ##### Creating a substring from-to
+  * ##### Creating a substring from ... to ...
     You can however, also create a substring starting at some index, and ending at another index by using the `substring((char*) string, int start, int end)` function.
 
     It is to note, that the range of the substring will be **[start;end[**.
@@ -149,6 +198,319 @@ You can create substrings in two different ways:
 
     ![exa6_output](media/06.JPG)
 
+#### Getting the index of a character
+
+You might want to get the index of a specific character in a string, in order to do this, you can use the following functions:
+  * ##### First index of character
+    In order to get the index of the first occurrence of the character, use the `indexOf((char*) str, (char) c)` function.
+
+    ```C
+    // ...
+
+    char* str = newstr("Hello World!");
+    int index = indexOf(str, 'o');
+
+    printf("First index: %d\n", index);
+
+    // ...
+    ```
+
+    ![exa7_output](media/07.JPG)
+
+  * ##### First index of character from ...
+    Sometimes, you might want to get the first occurrence of a character from a certain index. You can use the `indexOfFrom((char*) str, (char) c)` function to achieve this.
+
+    ```C
+    // ...
+
+    char* str = newstr("0123456789 0123456789");
+    int fIndex = indexOfFrom(str, '0', 10);
+
+    printf("First index from: %d\n", fIndex);
+
+    // ...
+    ```
+
+    ![exa9_output](media/09.JPG)
+
+  * ##### Last index of character
+    If you need to get the last index of the character, use the `lastIndexOf((char*) str, (char) c)`, which searches the string from the end.
+
+    ```C
+    // ...
+
+    char* str = newstr("This sentence has many 'a's ... ");
+    int lIndex = lastIndexOf(str, 'a');
+
+    printf("Last index: %d\n", lIndex);
+
+    // ...
+    ```
+
+    ![exa8_output](media/08.JPG)
+
+**Note:** All `indexOf...()` functions return a value of `-1` if no match was found.
+
+#### Getting the index of a substring
+
+All functions that are available for characters are also available for substrings.
+  * ##### First index of substring
+    In order to get the index of the first occurrence of the string, use the `indexOfString((char*) str, (char*) sub)` function.
+
+    ```C
+    // ...
+
+    char* str = newstr("Hello World!");
+    int index = indexOfString(str, "World!");
+
+    printf("First index: %d\n", index);
+
+    // ...
+    ```
+
+    ![exa10_output](media/10.JPG)
+
+  * ##### First index of substring from ...
+    Sometimes, you might want to get the first occurrence of a  string from a certain index. You can use the   `indexOfStringFrom((char*) str, (char*) sub)` function to achieve this.
+
+    ```C
+    // ...
+
+    char* str = newstr("0123456789 0123456789");
+    int fIndex = indexOfStringFrom(str, "89", 10);
+
+    printf("First index from: %d\n", fIndex);
+
+    // ...
+    ```
+
+    ![exa11_output](media/11.JPG)
+
+  * ##### Last index of substring
+    If you need to get the last index of the substring, use the   `lastIndexOfString((char*) str, (char*) sub)`, which searches the string from the end.
+
+    ```C
+    // ...
+
+    char* str = newstr("asdf hello hello asdf");
+    int lIndex = lastIndexOfString(str, "hello");
+
+    printf("Last index: %d\n", lIndex);
+
+    // ...
+    ```
+
+    ![exa12_output](media/12.JPG)
+
+**Note:** All `indexOfString...()` functions return a value of `-1` if no match was found.
+
+#### Occurrence of a character
+
+To get the amount of times a certain character appears in your string, use the `charOccurrence((char*) str, (char) c)` function.
+
+```C
+// ...
+
+char* mystr = newstr("asjdflasdjdfkljaskldasdfaaaasdfasdfa");
+int amount = charOccurrence(mystr, 'a');
+
+printf("Amount of 'a's: %d\n", amount);
+
+// ...
+```
+
+![exa13_output](media/13.JPG)
+
+#### Occurrence of a substring
+
+To get the amount of times a specified substring appears in your string, use the `stringOccurrence((char*) str, (char*) sub)` function.
+
+```C
+// ...
+
+char* mystr = newstr("asdf qwer asdf qwer asdf qwer asdf qwer");
+int amount = stringOccurrence(mystr, "asdf");
+
+printf("Amount of substrings: %d\n", amount);
+
+// ...
+```
+
+![exa14_output](media/14.JPG)
+
+#### Split at character
+
+To split a string at a specified character, you can use the `split((char*) str, (char) c)` function.
+
+This will return a reference to a char-pointer (the first part). You should combine this with the `charOccurrence(...)` function, to figure out, how many parts there are.
+
+```C
+// ...
+
+char* mystr = newstr("Hello! I'm Matthias ... Wow, this sentence is seemingly endless ...");
+
+int amount = charOccurrence(mystr, ' ')+1;
+char** parts = split(mystr, ' ');
+
+for (int i = 0; i < amount; i++) {
+  printf(" [%02d]: %s\n", i, parts[i]);
+}
+
+// ...
+```
+
+![exa15_output](media/15.JPG)
+
+#### Split at substring
+
+To split a string at a specified substring, you can use the `splits((char*) str, (char*) c)` function.
+
+You should handle it the same way, as the `split(...)` function's return value.
+
+```C
+// ...
+
+char* mystr = newstr("Hello!\r\nasdf\r\nqwer\r\n...\r\nWow,\r\nthis\r\nsentence\r\nis\r\nseemingly\r\nendless\r\n...");
+
+int amount = stringOccurrence(mystr, "\r\n")+1;
+char** parts = splits(mystr, "\r\n");
+
+for (int i = 0; i < amount; i++) {
+  printf(" [%02d]: %s\n", i, parts[i]);
+}
+
+// ...
+```
+
+![exa16_output](media/16.JPG)
+
+#### Convert to lowercase
+
+There are two ways to convert a string to lowercase:
+  1. ##### Lowercase copy
+    The first, possible way would be to use the `lowerCase((char*) str)` function, which returns a lowercase-copy of the specified string. This is useful, if you don't want to modify the original "string".
+
+    ```C
+    // ...
+
+    char* mystr = newstr("Hello World!");
+    char* strLow = lowerCase(mystr);
+
+    printf("Lowercase: %s\n", strLow);
+    printf("Original: %s\n", mystr);
+
+    // ...
+    ```
+
+    ![exa17_output](media/17.JPG)
+
+  2. ##### Value to lowercase
+    The second option would be, to convert the value of your "string" to lowercase using the `toLowerCase((char*) str)` function.
+
+    ```C
+    // ...
+
+    char* str = newstr("Hello everyone!");
+    toLowerCase(str);
+
+    printf("Original-lowercase: %s\n", str);
+
+    // ...
+    ```
+
+    ![exa18_output](media/18.JPG)
+
+    **Note:** When using the `toLowerCase(...)` function, it's necessary, that your string was created dynamically.
+
+#### Convert to uppercase
+
+There are also two ways to convert a string to uppercase:
+  1. ##### Uppercase copy
+    Similiar to the `lowerCase(...)` function, you can use the `upperCase((char*) str)`, which also returns a copy, but in this case the copy is in upper-case.
+
+    ```C
+    // ...
+
+    char* str = newstr("Hello World!");
+    char* upp = upperCase(str);
+
+    printf("Uppercase: %s\n", upp);
+    printf("Original: %s\n", str);
+
+    // ...
+    ```
+
+    ![exa19_output](media/19.JPG)
+
+  2. ##### Value to uppercase
+    The second option, once again, converts the value of the "string" to uppercase. Use the `toUpperCase((char*) str)` function for this.
+
+    ```C
+    // ...
+
+    char* mystr = newstr("Lorem Ipsum");
+    toUpperCase(mystr);
+
+    printf("Original-uppercase: %s\n", mystr);
+
+    // ...
+    ```
+
+    ![exa20_output](media/20.JPG)
+
+    **Note:** When using the `toUpperCase(...)` function, it's necessary, that your string was created dynamically.
+
+#### Replace all characters
+
+You can use the `replace((char*) str, (char) c, (char) r)` function to replace all occurrences of the given character `c` with the specified character `r`.
+
+```C
+// ...
+
+char* mystr = newstr("Hello World!");
+replace(mystr, 'o', 'a');
+
+printf("String: %s\n", mystr);
+
+// ...
+```
+
+![exa21_output](media/21.JPG)
+
+#### Replace all substrings
+
+You can use the `replaceString((char*) str, (char*) s, (char*) r)` function to replace all occurrences of the given substring `s` with the specified substring `r`.
+
+```C
+// ...
+
+char* mystr = newstr("Hello World!");
+mystr = replaceString(mystr, "World", "Humans");
+
+printf("String: %s\n", mystr);
+
+// ...
+```
+
+![exa22_output](media/22.JPG)
+
+#### Trim whitespace
+
+Use the `trim((char*) str)` function to trim all whitespace from the beginning and end of a string.
+
+```C
+// ...
+
+char* msg = newstr("      \n\rHello World!\n     ");
+char* trimmed = trim(msg);
+
+printf("Trimmed: %s\n", trimmed);
+
+// ...
+```
+
+![exa23_output](media/23.JPG)
+
 **-- to be continued --**
 
 ## Conclusion