Getting "command not found" error while comparing two strings in Bash

Question

My whole Script is currently this:

#!/bin/sh    clear;    blanko="";    # Dummy-Variablen variable=Testvariable;    if [[$variable == $blanko]]; then      echo "Nichts da!"    else      echo $variable    fi 

and if i enter

TestSelect.sh 

i get

/usr/bin/TestSelect.sh: line 6: [[Testvariable: command not found    Testvariable 

how can i fix this?

Answer 1

This is problem:

if [[$variable == $blanko]]; 

Spaces are required inside square brackets, use it like this:

[[ "$variable" == "$blanko" ]] && echo "Nichts da!" || echo "$variable"