Empty String

Checking if a string is empty or not is a basic programming need. The effective way to check if a string is empty or not is to use the Length property of the string class, instead of using null or comparing with " " string.

string str1 = AMethodReturnsString()
{
// Do something and return a string
}
if (str1.Length >0 )
{
// do something
}

String Concatenation

Whenever you modify a String it returns a new string as the result. Creating many String objects might degrade the performance of your program. You can avoid creating a new instance of String by using the StringBuilder class.

Say you want to concatenate two strings. Here is the traditional way -

string str1 = "I like ";
string str2 = "Soccer";
string strConcat = string.Concat(str1, str2);

The value of strConcat = "I like Soccer". You can use the StringBuilder class and its Append method to do the same.

StringBuilder MyStrBuilder = new StringBuilder ("I like ");
String newStr = "Soccer";
MyStrBuilder.Append(newStr);

The value of MyStrBuilder is "I like Soccer".

Comparing String

Use string.Equals method to compare two strings.

string str1 = AMethodReturnsString()
if (str1.Equals("TestSting") )
{
// do something
}